Control unit for vehicle

Abstract

To provide a control unit for a vehicle capable of safely continuing failsafe driving with a shift range determined with a non-failed sensor, in a case that any of a plurality of sensors has failed.SOLUTION: An ECU identifies a failed sensor when a single failure in which a detection signal of one of a plurality of sensors becomes an abnormal value due to failure (No in step S3), by comparing with a normal case map defining a normal case output pattern consisting of detection signals with normal values, determines a shift range based on detection signals of remaining sensors within the plurality of sensors, and performs first failsafe which permits traveling with the determined shift range (step S4).SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a control device for a vehicle.

Background Art

[0002] Patent Document 1 describes a vehicle shift control device that switches to a fail-safe mode in which a retreat running in the N range is performed when an abnormality occurs in a shift sensor during running in the D range (forward running range), and when the shift sensor returns to a normal state during the retreat running in the N range, it automatically switches to the normal control mode and resumes running in the D range.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the technology described in Patent Document 1, the fail-safe when an abnormality occurs in the shift sensor is a retreat running in the N range, and it is limited to running until stopping on the road shoulder, so it is not possible to continue running to the repair base, and there is a problem of impairing convenience.

[0005] The present invention has been made paying attention to the above circumstances, and an object of the present invention is to provide a control device for a vehicle that can safely continue fail-safe running in a shift range determined by a sensor that has not failed when any one of a plurality of sensors fails.

Means for Solving the Problems

[0006] The present invention relates to a vehicle control device including a select lever that is moved by a driver so as to select any one of a plurality of shift ranges sequentially arranged adjacent to each other, and a detection signal that is turned on or off according to the position of the select lever in the selected shift range, and a plurality of sensors arranged such that output patterns formed by combinations of on or off of the detection signals are different from each other in the plurality of shift ranges, and a control unit that determines the selected shift range based on the detection signal. When a single failure occurs in which the detection signal of any one of the plurality of sensors becomes an abnormal value due to a failure, the control unit identifies the failed sensor by comparing it with a normal-time map that defines a normal-time output pattern composed of the detection signals of normal values, determines the shift range based on the detection signals of the remaining sensors among the plurality of sensors, and implements a first fail-safe that permits traveling in the determined shift range.

Advantages of the Invention

[0007] As described above, according to the present invention, when any one of a plurality of sensors fails, it is possible to provide a vehicle control device that can safely continue fail-safe driving in a shift range determined by sensors that have not failed.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

[0009] A vehicle control device according to an embodiment of the present invention includes a select lever that is moved by a driver to select any one of a plurality of shift ranges arranged adjacent to each other in sequence, a plurality of sensors that output a detection signal that is turned on or off according to the position of the select lever in the selected shift range, and the output patterns, which are combinations of on or off of the detection signals, are arranged to be different from each other in the plurality of shift ranges, and a control unit that determines the selected shift range based on the detection signal. The control unit, when a single failure occurs in which the detection signal of any one of the plurality of sensors becomes an abnormal value due to a failure, identifies the failed sensor by comparing it with a normal-time map that defines an output pattern during normal times consisting of detection signals of normal values, determines the shift range based on the detection signals of the remaining sensors of the plurality of sensors, and implements a first fail-safe that permits traveling in the determined shift range. Accordingly, the vehicle control device according to an embodiment of the present invention can safely continue fail-safe traveling in the shift range determined by the sensors that have not failed when any one of the plurality of sensors fails. EXAMPLE

[0010] Hereinafter, with reference to the drawings, a vehicle equipped with a vehicle control device according to an embodiment of the present invention will be described.

[0011] As shown in FIG. 1, the vehicle 1 includes a power train 2, a differential device 5, left and right drive wheels 6, a shift range switching device 10, an ECU 20 as a control unit, and a warning device 30. The power train 2 is composed of an engine 3 and an automatic transmission 4. The shift range switching device 10 and the ECU 20 constitute a shift position detection device.

[0012] The shift range switching device 10 includes a select lever 11 operated by the driver, a magnet 12 that moves in conjunction with the select lever 11, and a plurality (eight in this embodiment) of sensors H1 to H8. The select lever 11 is moved by the driver to select any one of a plurality of shift ranges arranged adjacent to each other in sequence. The plurality of sensors H1 to H8 output detection signals that are on or off according to the position of the select lever (the position of the select lever 11) in the selected shift range, and are arranged such that the output patterns composed of the on or off combinations of the detection signals are different for the plurality of shift ranges.

[0013] The shift position detection device detects the position (shift position) of the select lever 11 based on the outputs of the plurality of sensors H1 to H8, and determines the shift range selected by the driver. The shift ranges selected by the select lever 11 in the shift range switching device 10 include a P range which is a parking position, an R range which is a reverse position, an N range which is a neutral position, a D range and an M range which are forward positions. The D range is a shift range in which automatic shifting is performed. The M range is a shift range in which manual shifting is performed by the driver operating an operation unit (not shown) for upshifting and downshifting. These five shift ranges of the P range, R range, N range, D range, and M range are arranged adjacent to each other in sequence. In this specification, the shift range is also referred to as the shift position.

[0014] The select lever 11 is moved by the driver so as to select any one of a plurality of shift ranges. Specifically, the select lever 11 is operated so as to swing in the longitudinal direction of the vehicle with its base (lower end) as the swing center.

[0015] The magnet 12 moves back and forth in the vicinity of the sensors H1 to H8 so as to switch the outputs of the sensors H1 to H8 in conjunction with the swing of the select lever 11. For the purpose of the image diagram, the magnet 12 is shown as a vertical straight line in FIG. 2. The moving direction of the magnet 12 is the left-right direction in FIG. 2, and shows the relationship between the positions of the magnet 12 at each shift range position and the intermediate position and the outputs of the sensors H1 to H8.

[0016] The sensors H1 to H8 output on or off detection signals according to the shift range selected by the select lever 11. Further, the sensors H1 to H8 invert the on or off detection signals at the intermediate positions between the shift ranges as the select lever 11 moves. Specifically, the outputs of the sensors H1 to H8 are switched by the magnet 12 that moves in conjunction with the swing of the select lever 11. By the combination of the outputs of the respective sensors H1 to H8, a predetermined output pattern will be output at each shift range and the intermediate position.

[0017] The sensors H1 to H8 are composed of single or multiple Hall elements, and output an on detection signal when the magnet 12 is close, and output an off detection signal when the magnet 12 is not close. Although it is assumed that an off detection signal is output, as the detection signal, a signal indicating that the magnet 12 is close may be output when it is on, and no signal may be output when it is off when the magnet 12 is not close.

[0018] Among the eight sensors H1 to H8 of the system, sensors H1, H3, H4, and H5 have a range where the output signal turns off (the moving range of the select lever 11) between a plurality of on output signals as shown in FIG. 2. The remaining sensors H2, H6 to H8 have a range of a single on output signal. In this way, the shift range switching device 10 is configured to detect five shift positions by the eight sensors H1 to H8. In addition, in order to output a plurality of on output signals like sensors H1, H3, H4, and H5, two Hall elements may be arranged along the moving path of the magnet 12, or the magnet 12 may be configured to pass by a single Hall element in the vicinity a plurality of times in sequence. When a failure of the Hall element is a concern, a plurality of magnets 12 or a magnet 12 with an irregular shape may be used.

[0019] Sensors H1 to H8 are arranged on the moving path of the magnet 12 and face the magnet 12 moving on the moving path. The shape of the magnet 12 is arranged according to the range where it is desired to output an on output signal to sensors H1 to H8 within the moving range of the select lever 11. For example, the magnet 12 has a portion with a short length along its moving direction and a portion with a long length along its moving direction. A part of sensors H1 to H8 is arranged on the moving path of the short portion of the magnet 12, and the rest of sensors H1 to H8 is arranged on the moving path of the long portion of the magnet 12.

[0020] Sensors H1 to H8 output an on signal or an off detection signal according to the position of the magnet 12 respectively. In each shift range, an output pattern composed of the on or off combination of the detection signals of each of sensors H1 to H8 is output. Sensors H1 to H8 are arranged so that the output patterns are different from each other in a plurality of shift ranges.

[0021] The ECU20 as the control unit treats and processes the detection signals of each of the sensors H1 to H8 as an 8-bit (8-digit) binary output pattern. Specifically, the ECU20 treats and processes the detection signals of each of the sensors H1 to H8 as an output pattern arranged in descending order from the most significant digit. For example, when the detection signals of the sensors H1 to H8 are 1, 0, 0, 0, 1, 1, 0, 0 respectively, the output pattern is "10001100".

[0022] The ECU20 is composed of a computer unit including a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, an input port, and an output port.

[0023] In the ROM of the computer unit, a program for causing the computer unit to function as the ECU20 is stored together with various constants and various maps. That is, in the computer unit, when the CPU executes the program stored in the ROM, the computer unit functions as the ECU20 in the present embodiment.

[0024] The shift range switching device 10 and the like are connected to the input port of the ECU20. Various control targets including the engine 3, the automatic transmission 4, and the warning device 30 are connected to the output port of the ECU20.

[0025] The ECU 20 constantly monitors the output patterns of sensors H1 to H8 not only at each shift range but also at the intermediate position of the select lever 11, and determines the shift range selected by the select lever 11 based on the output patterns of sensors H1 to H8. When all of the sensors H1 to H8 are normal without any failure, the output pattern in each shift range does not overlap with the output pattern in any other shift range or the output pattern at the intermediate position, and it is not necessary to determine whether the driver's selection operation has been completed (i.e., not at the intermediate position), and the shift range can be easily identified. Note that there may be an overlap between the output patterns at the intermediate position. Specifically, the output pattern is obtained from the detection signals of sensors H1 to H8 and compared with the normal output patterns (the output patterns in each shift range and the output patterns at each intermediate position) when all of the sensors H1 to H8 are normal without any failure to determine the selected shift range. Note that, in order to facilitate control, the ECU 20 uses the signals received from sensors H1 to H8 as an 8-bit binary output pattern, converts it to a decimal number internally, and performs an operation to search for a value (the position of the select lever 11 such as the shift range) that matches this decimal number from a normal-time map (a list of output patterns that may appear during normal operation). If there is no value in the normal-time map that matches the output pattern of the signals received from sensors H1 to H8, it is determined that one of the eight sensors H1 to H8 is faulty. That is, the ECU 20 constantly monitors the output patterns of sensors H1 to H8, compares them with the normal-time map not only at each shift range but also at the intermediate position, checks whether the output pattern is abnormal, and determines whether there is any sensor failure in the eight sensors H1 to H8.

[0026] As will be described later, when the ECU 20 detects an abnormal output pattern due to a failure of any one of the eight sensors H1 to H8, the ECU 20 identifies the failed sensor. Then, the ECU 20 determines the shift range based on the output patterns of the seven normal sensors excluding the failed sensor. That is, the ECU 20 treats the detection signal of the failed sensor as equivalent to either "0" or "1", and continues to determine the shift range using the outputs of the seven normal sensors. Since the ECU 20 can identify the shift range selected by the driver even when an abnormal output pattern is detected, it does not perform safety control to immediately prohibit driving, but warns the user by lighting the warning device 30 that any one of the sensors H1 to H8 is faulty.

[0027] As described above, the ECU 20 stores the output patterns during the normal operation of sensors H1 to H8 as a normal-time map, and determines the position of the select lever 11 and the selected shift range by referring to this normal-time map. The ECU 20 also stores an abnormal-time map to be used when sensors H1 to H8 malfunction. The abnormal-time map is provided for each malfunctioning sensor. For example, the ECU 20 stores abnormal-time maps to be used when only sensor H1 malfunctions, when only sensor H2 malfunctions, and so on, for each malfunction of sensors H1 to H8. When a malfunction of any one of sensors H1 to H8 is determined, an abnormal-time map obtained by adding the output pattern when one sensor malfunctions in each shift range to the normal-time map is referred to, and the position of the select lever 11 and the selected shift range are determined. After identifying the malfunctioning sensor, the ECU 20 continues to determine the shift position by referring to the abnormal-time map for determining the position of the select lever 11 and the selected shift range without using this malfunctioning sensor. The output pattern when one sensor malfunctions in each shift range is set so as not to overlap with the output pattern when one sensor malfunctions in other shift ranges and the output pattern in each normal shift range. Therefore, when one sensor malfunctions, the lever position (selected shift range) can be estimated (since the output pattern at the intermediate position is detected for a short time). At this time, although the malfunctioning sensor may be identified in some cases, it is not always possible to identify it because the output pattern when one sensor malfunctions in each shift range may overlap with the output pattern at the intermediate position or the normal-time output pattern.

[0028] As shown in FIG. 2, for the output states of sensors H1 to H8, there are an on range that outputs an on signal (1) (denoted as ON RANGE in the figure), a switching range provided at both ends of this on range (denoted as CHANGEOVER RANGE in the figure), and an off range that outputs an off signal (0) (denoted as OFF RANGE in the figure). The switching range is the range where the detection signal switches from off to on or from on to off (the range where the inversion of the output is surely performed), and is determined in consideration of the individual differences and mounting errors of the sensors. Also, at each position of the P range, R range, N range, D range, and M range, an assembly tolerance range (denoted as ASSY TOLERANCE RANGE in the figure) is set in consideration of the mounting errors of the select lever 11 and the magnet 12.

[0029] At the position of the P range, the on ranges of sensors H1, H5, and H6 are arranged. When the P range is selected, sensors H1, H5, and H6 turn on (1), and the other sensors turn off (0). Therefore, the output pattern of sensors H1 to H8 becomes "10001100" (see FIG. 3).

[0030] At the position of the R range, the on ranges of sensors H2, H3, H4, and H6 are arranged. When the R range is selected, sensors H2, H3, H4, and H6 turn on (1), and the other sensors turn off (0). Therefore, the output pattern of sensors H1 to H8 becomes "01110100" (see FIG. 3).

[0031] At the position of the N range, the on ranges of sensors H1, H2, H4, H5, and H7 are arranged. When the N range is selected, sensors H1, H2, H4, H5, and H7 turn on (1), and the other sensors turn off (0). Therefore, the output pattern of sensors H1 to H8 becomes "11011010" (see FIG. 3).

[0032] At the position of the D range, the on ranges of sensors H3, H7, and H8 are arranged. When the D range is selected, sensors H3, H7, and H8 turn on (1), and the other sensors turn off (0). Therefore, the output pattern of sensors H1 to H8 becomes "00100011" (see FIG. 3).

[0033]

[0033] The on ranges of sensors H4 and H8 are arranged at the position of the M range. When the M range is selected, sensors H4 and H8 turn on (1), and the other sensors turn off (0). Therefore, the output pattern of sensors H1 to H8 becomes "00010001" (see Figure 3).

[0034] Intermediate positions that do not belong to any shift position are provided between the positions of the P range, R range, N range, D range, and M range, respectively. At this intermediate position, the detection signals of sensors H1 to H8 are switched, and the output pattern changes (see Figure 3).

[0035] The switching ranges of five sensors H1, H2, H3, H4, and H5 and the on range of one sensor H6 are arranged at the intermediate position between the P range and the R range (hereinafter also referred to as the P-R intermediate position). Therefore, at the P-R intermediate position, the output states of sensors H1, H2, H3, H4, and H5 are inverted and switched, and sensor H6 maintains the on state.

[0036] The switching ranges of five sensors H1, H3, H5, H6, and H7 and the on ranges of two sensors H2 and H4 are arranged at the intermediate position between the R range and the N range (hereinafter also referred to as the R-N intermediate position). Therefore, at the R-N intermediate position, the output states of sensors H1, H3, H5, H6, and H7 are inverted and switched, and sensors H2 and H4 maintain the on state.

[0037] The switching ranges of six sensors H1, H2, H3, H4, H5, and H8 and the on range of one sensor H7 are arranged at the intermediate position between the N range and the D range (hereinafter also referred to as the N-D intermediate position). Therefore, at the N-D intermediate position, the output states of sensors H1, H2, H3, H4, H5, and H8 are inverted and switched, and sensor H7 maintains the on state.

[0038] At an intermediate position between the D range and the M range (hereinafter also referred to as the D-M intermediate position), there are arranged the switching ranges of three sensors H3, H4, H7 and the on range of one sensor H8. For this reason, at the D-M intermediate position, the output states of sensors H3, H4, H7 are inverted and switched, and sensor H8 maintains the on state.

[0039] In this way, for sensors H1 to H8, the number of sensors (three sensors H3, H4, H7) whose output states are switched during the process of the select lever 11 moving through the intermediate position (D-M intermediate position) between the D range and the M range as the shift ranges constituting the forward driving range is less than the number of sensors whose output states are switched during the process of the select lever 11 moving through each intermediate position (P-R intermediate position, R-N intermediate position, N-D intermediate position) between the P range, R range, and N range as the shift ranges constituting the non-forward driving range. Conversely, when switching between parking and driving or when switching the driving direction, the number of sensors whose output states are switched is increased compared to when switching between ranges in the same driving direction (for example, the D range and the M range). In particular, when switching between the R range and the D range, due to the arrangement of the N range in the middle, the output states of a large number of sensors are inverted.

[0040] As shown in FIG. 3, the output pattern of the normal-time map of sensors H1 to H8 represented by an 8-bit binary number (denoted as BIN in the figure) includes one output pattern generated at each shift position of the P range, R range, N range, D range, and M range.

[0041] In addition, the output patterns of the normal-time maps of sensors H1 to H8 include five output patterns generated at the intermediate position between P and R, 15 output patterns generated at the intermediate position between R and N, 31 output patterns generated at the intermediate position between N and D, and three output patterns generated at the intermediate position between D and M. The output patterns generated at the intermediate positions are set to be different from the output patterns generated at each shift position in the P range, R range, N range, D range, and M range. In FIG. 3, the calculated value (DEC in the figure) converted from the binary number is used for the calculation in the ECU 20.

[0042] Sensors H1 to H8 are arranged to output a plurality of output patterns that do not overlap with the output patterns generated in each shift range at the intermediate positions between the shift lever positions (shift positions) in the state where each shift range is selected. Specifically, sensors H1 to H8 are arranged to output a plurality of output patterns that do not overlap with each shift range of the P range, R range, N range, D range, and M range at the intermediate positions between P and R, between R and N, between N and D, and between D and M. Also, at the intermediate positions between P and R and between D and M, they are arranged to output a plurality of output patterns that do not overlap with other intermediate positions. Note that at the intermediate positions between R and N and between N and D, they are arranged to possibly output output patterns that overlap with other intermediate positions. These are determined in consideration of the degree of freedom of arrangement, reduction of the number of sensors, and the risk of malfunctions in the vehicle.

[0043] Also, sensors H1 to H8 are arranged such that the output pattern changes in a predetermined order as the selection lever 11 moves through the intermediate position between adjacent shift ranges. For example, when switching from the P range to the R range, the output pattern changes to 11001100, 01001100, 11101100, 01101100, 01111100 at the P-R intermediate position. Specifically, as shown by the arrows in FIG. 2, the switching ranges of the respective sensors H1 to H8 are determined in relation to each other. Therefore, the sensors H1 to H8 are arranged such that their outputs change in a predetermined order. For example, during the process of changing from the P range to the R range, the selection lever 11 moves out of the P range position (the shift position range where the output pattern indicating the P range is output) and passes through a predetermined movement amount (the range of the arrow) to enter the switching range of sensor H2. After the switching range of this sensor H2 ends and the switching of sensor H2 is surely completed, it passes through a predetermined movement amount (the range of the arrow) to enter the switching ranges of sensors H1 and H3. After the switching ranges of sensors H1 and H3 end and the switching of sensors H1 and H3 is surely completed, it passes through a predetermined movement amount to enter the switching range of sensor H4. After the switching range of this sensor H4 ends and the switching of sensor H4 is surely completed, it passes through a predetermined movement amount to enter the switching range of sensor H5. And after the switching of sensor H5 is surely completed, it is set such that the selection lever 11 passes through a predetermined movement amount to reach the R range position (the shift position range where the output pattern indicating the R range is output). Not only at the P-R intermediate position, but also at the R-N intermediate position, N-D intermediate position, and D-M intermediate position, the order of the switching ranges of the respective sensors H1 to H8 is determined as shown by the arrows in FIG. 2. Since the switching order of the respective sensors H1 to H8 is determined, the assumed normal output pattern can be reduced in number as shown in FIG. 3, and it is possible to confirm whether the transition of the output pattern is also a transition of the normal output pattern, although it is approximate.

[0044] In addition, in order to make the swing range between each range of the select lever 11 appropriate, the switching order is not determined for all sensors that switch between each range, and many switching orders are set in the process of changing from the P range with a relatively large movement amount to the R range. In other words, by making the number of sensors for setting the switching order appropriate, the operation amount of the select lever 11 between each range can be made appropriate.

[0045] Sensors H1 to H8 are arranged such that when a failure (single failure) occurs in which any one of the plurality of sensors H1 to H8 always outputs either on or off due to a failure, at least one shift range among the plurality of shift ranges can identify the failed sensor. That is, when an abnormal output pattern that does not exist in the normal output pattern, including during the movement operation of the select lever 11, is detected, and if the abnormal output pattern continues, it is assumed that one of the sensors has failed and compared with the output pattern stored in the abnormal map to identify the failed sensor. Also, sensors H1 to H8 are arranged so as to be able to identify whether the failed sensor is in an on-failure state where it always outputs on or an off-failure state where it always outputs off. This is made possible by the fact that in at least one shift range, the output pattern (abnormal output pattern) in the state where one of the sensors has failed does not exist in the normal output pattern, including during the movement operation of the select lever 11. That is, since the abnormal output pattern is an output pattern that occurs only when a specific sensor has failed in a predetermined shift range, the failed sensor can be identified. In this embodiment, since the switching order of each sensor H1 to H8 is determined, the assumed normal output pattern can be reduced, the abnormal output pattern can be detected relatively easily, and the overlap of the output patterns in the state where one of the sensors has failed can also be reduced. Also, since the output patterns are made different for the sensor outputs in each range, there will be no confusion or misrecognition due to a single failure. When it is assumed that the output of one sensor is abnormal, the shift range selected by the remaining sensors can be estimated. At this time, the detected abnormal output pattern is compared with the output pattern stored in the abnormal map to identify the failed sensor.

[0046] For example, in the P range, when sensor H1 has an off-failure, the detection signal of sensor H1 is always "0". Therefore, an abnormal output pattern "00001100" is output instead of the normal output pattern "10001100". In this case, this abnormal output pattern does not overlap with any of the normal output patterns. Furthermore, this abnormal output pattern is also different from the output patterns in the state where one of the sensors in other shift ranges has failed. For this reason, when the abnormal output pattern "00001100" is output, it can be determined that it is the P range where sensor H1 has an off-failure. Also, the calculated value in decimal is 12, but this calculated value does not overlap with any of the calculated values of the normal output patterns. Whether the abnormal output pattern due to a failure overlaps with the normal output pattern can be determined not only based on the 8-bit binary output pattern but also based on the calculated value in decimal. In this way, the off-failure of sensor H1 can be determined in the P range. That is, in the state where the shift position of the P range is selected, it can be specified that sensor H1 has failed in the mode of off-failure.

[0047] Similarly, in the P range, when sensor H5 or H6 has an off-failure, and when any one of sensors H3, H4, H7, H8 has an on-failure, the abnormal output pattern does not overlap with any of the normal output patterns, and is also different from the output pattern in the state where one of the sensors in other shift ranges has failed. Therefore, when these abnormal output patterns are detected, it can be determined that sensor H5 or H6 has failed in the mode of off-failure and that it is in the P range, and it can be determined that any one of sensors H3, H4, H7, H8 has failed in the mode of on-failure and that it is in the P range. On the other hand, in the P range, when sensor H2 has an on-failure, the abnormal output pattern overlaps with the normal output pattern. When this sensor H2 has an on-failure, the operation value becomes 204 with the abnormal output pattern "11001100", but although it is not a normal output pattern in each shift range, this operation value overlaps with the normal value generated at the P-R intermediate position. Therefore, with this output pattern, it cannot be discriminated from the output pattern at the P-R intermediate position, and the on-failure of sensor H2 cannot be determined in the P range.

[0048] Also, in the R range, when any one of sensors H2, H3, H4, H6 has an off-failure, and when either one of sensors H1, H8 has an on-failure, the abnormal output pattern does not overlap with any of the normal output patterns, and is also different from the output pattern in the state where one of the sensors in other shift ranges has failed. Therefore, when these abnormal output patterns are detected, it can be determined that any one of sensors H2, H3, H4, H6 has failed in the mode of off-failure and that it is in the R range, and it can be determined that either one of sensors H1, H8 has failed in the mode of on-failure and that it is in the R range. On the other hand, in the R range, when either one of sensors H5, H7 has an on-failure, the abnormal output pattern overlaps with the normal output pattern. Therefore, with these output patterns, it cannot be discriminated from the output pattern at the intermediate position, and the on-failure of either one of sensors H5, H7 cannot be determined in the R range.

[0049] Also, in the N range, when sensor H7 has an off-failure, the abnormal output pattern does not overlap with any of the normal output patterns and is also different from the output patterns in the state where one of the sensors in other shift ranges has failed. Therefore, when this abnormal output pattern is detected, it can be specified that sensor H7 has failed in the mode of off-failure and that it is in the N range. On the other hand, in the N range, when sensors H1, H2, H4, H5 have off-failures and when sensors H3, H6, H8 have on-failures, the abnormal output pattern overlaps with the normal output pattern. Therefore, these output patterns cannot be discriminated from the output pattern at the intermediate position, and in the N range, the off-failures of sensors H1, H2, H4, H5 and the on-failures of sensors H3, H6, H8 cannot be determined.

[0050] Also, in the D range, when any one of sensors H3, H7, H8 has an off-failure and when any one of sensors H2, H5, H6 has an on-failure, the abnormal output pattern does not overlap with any of the normal output patterns and is also different from the output patterns in the state where one of the sensors in other shift ranges has failed. Therefore, when these abnormal output patterns are detected, it can be specified that any one of sensors H3, H7, H8 has failed in the mode of off-failure and that it is in the D range, and it can be specified that any one of sensors H2, H5, H6 has failed in the mode of on-failure and that it is in the D range. On the other hand, in the D range, when either of sensors H1, H4 has an on-failure, the abnormal output pattern overlaps with the normal output pattern. Therefore, these output patterns cannot be discriminated from the output pattern at the intermediate position, and in the D range, the on-failure of sensors H1, H4 cannot be determined.

[0051] Also, in the M range, if either of the sensors H4 or H8 has an off-failure, and if any of the sensors H1, H2, H5, or H6 has an on-failure, the abnormal output pattern does not overlap with any of the normal output patterns and is also different from the output pattern in the state where one of the sensors in other shift ranges has failed. Therefore, when these abnormal output patterns are detected, it can be specified that either of the sensors H4 or H8 has failed in the mode of off-failure and that it is the M range, and it can be specified that any of the sensors H1, H2, H5, or H6 has failed in the mode of on-failure and that it is the M range. On the other hand, in the M range, when the sensors H3 and H7 have an on-failure, the abnormal output pattern overlaps with the normal output pattern. Therefore, with these output patterns, it is impossible to distinguish from the output pattern at the intermediate position, and it is impossible to determine the on-failure of the sensors H3 and H7 in the M range.

[0052] In this way, for example, the on-failure of the sensor H2 cannot be determined in the P range but can be determined in the D range or the M range. Similarly, when a single failure occurs in which any one of the sensors H1 to H8 fails, even if it is impossible to determine the failure due to overlap with the normal output pattern in a certain shift range (shift position), it is possible to determine which sensor has failed in at least one of the other remaining shift ranges.

[0053] Here, when a failure occurs in any one of the sensors H1 to H8 and an abnormal output pattern is detected, sorting out the possibility of failure determination for each sensor results in the following.

[0054] The off-failure of the sensor H1 cannot be determined in the N range but can be determined in the P range. The on-failure of the sensor H1 cannot be determined in the D range but can be determined in the R range and the M range.

[0055] The off-failure of the sensor H2 can be determined in the R range. The on-failure of the sensor H2 cannot be determined in the P range but can be determined in the D range and the M range.

[0056] The off-fault of sensor H3 can be determined in the R range and D range. The on-fault of sensor H3 cannot be determined in the N range and M range, but can be determined in the P range.

[0057] The off-fault of sensor H4 cannot be determined in the N range, but can be determined in the R range and M range. The on-fault of sensor H4 cannot be determined in the D range, but can be determined in the P range.

[0058] The off-fault of sensor H5 cannot be determined in the N range, but can be determined in the P range. The on-fault of sensor H5 cannot be determined in the R range, but can be determined in the D range and M range.

[0059] The off-fault of sensor H6 can be determined in the P range and R range. The on-fault of sensor H6 cannot be determined in the N range, but can be determined in the D range and M range.

[0060] The off-fault of sensor H7 can be determined in the N range and D range. The on-fault of sensor H7 cannot be determined in the R range and M range, but can be determined in the P range.

[0061] The off-fault of sensor H8 can be determined in the D range and M range. The on-fault of sensor H8 cannot be determined in the N range, but can be determined in the P range and R range.

[0062] Sensors H1 to H8 are arranged such that when a single fault occurs, the number of sensors that can be judged to be faulty is greater in the non-N range than in the N range.

[0063] Specifically, among the sensors H1 to H8, the one that can identify a failure in the N range is only sensor H7 (off failure). On the other hand, in the P range which is a non-N range, the ones that can identify a failure are seven sensors: sensor H1 (off failure), sensor H3 (on failure), sensor H4 (on failure), sensor H5 (off failure), sensor H6 (off failure), sensor H7 (on failure), and sensor H8 (on failure). Also, in the R range which is a non-N range, the ones that can identify a failure are six sensors: sensor H1 (on failure), sensor H2 (off failure), sensor H3 (off failure), sensor H4 (off failure), sensor H6 (off failure), and sensor H8 (on failure). Further, in the D range which is a non-N range, the ones that can identify a failure are six sensors: sensor H2 (on failure), H3 (off failure), H5 (on failure), H6 (on failure), H7 (off failure), and H8 (off failure). Additionally, in the M range which is a non-N range, the ones that can identify a failure are six sensors: sensor H1 (on failure), sensor H2 (on failure), sensor H4 (off failure), sensor H5 (on failure), sensor H6 (on failure), and sensor H8 (off failure).

[0064] The change in the output pattern in a predetermined order at each intermediate position includes the change in the output pattern due to one of the sensors H1 to H8 switching on or off, and the change in the output pattern due to multiple sensors in a group switching on or off in any order. That is, to make the detection signals of the sensors change in a predetermined order, there are cases where the switching order is clearly determined for each of the sensors H1 to H8, and cases where some sensors are grouped together and the switching order with other sensors or groups is determined. And within this group, the switching order between the sensors is not restricted.

[0065] As shown in Fig. 2, specifically, when switching from the P range to the R range, the outputs of the five sensors are inverted, and the change in the output pattern in a predetermined order at the P-R intermediate position is composed of the change in the output pattern due to one sensor H2 switching on, followed by the change in the output pattern due to the sensors H1 and H3 in the group switching off and on respectively in any order, followed by the change in the output pattern due to one sensor H4 switching on, and then the change in the output pattern due to one sensor H5 switching off. Here, the change in the output pattern in any order in the group of H1 and H3 includes the case where sensor H3 turns on after sensor H1 turns off and the case where sensor H1 turns off after sensor H3 turns on. That is, all cases of (sensor H1: on, sensor H3: off), (sensor H1: on, sensor H3: on), (sensor H1: off, sensor H3: off), and (sensor H1: off, sensor H3: on) are considered. These normal output patterns are all summarized in Fig. 3 as the assumed normal output patterns.

[0066] Also, when switching from the R range to the N range, the outputs of the five sensors are inverted, and the change in the output pattern in a predetermined order at the R-N intermediate position is composed of the change in the output pattern due to one sensor H7 switching on, followed by the change in the output pattern due to the sensors H1, H3, H5, and H6 in the group switching on, off, on, and off respectively in any order. Since the switching in the group is in any order, the assumed normal output patterns are more than those at the P-R intermediate position.

[0067] Also, when switching from the N range to the D range, the outputs of the six sensors are inverted. The change in the output pattern in a predetermined order at the intermediate position between N and D consists of the change in the output pattern where, in the group of sensors H2, H3, H4, H5, H8, sensor H2 turns off, sensor H3 turns on, sensor H4 turns off, sensor H5 turns off, and sensor H8 turns on in any order, followed by the change in the output pattern where one sensor H1 turns off. Since the switching in the group occurs in any order, the assumed normal output pattern is more than that at the intermediate position between R and N. Between N and D, the outputs of many sensors are inverted to improve the detection accuracy in the D range. However, to suppress the swing angle of the select lever 11 for the purpose of improving operability, the switching order of the sensors is set as a group with any order.

[0068] Also, when switching from the D range to the M range, the outputs of three sensors are inverted. The change in the output pattern in a predetermined order at the intermediate position between D and M consists of the change in the output pattern where one sensor H4 turns on, followed by the change in the output pattern where, in the group of sensors H3 and H7, sensor H3 turns off and sensor H7 turns off in any order. The intermediate position between D and M has the fewest assumed normal output patterns compared to other intermediate positions.

[0069] Sensors H1 to H8 are arranged such that the change in the output pattern due to one sensor that is ordered individually rather than in a group among sensors H1 to H8 turning on or off is the largest at the intermediate position between the P range and the R range, i.e., the PR intermediate position. That is, the number of sensors whose switching order is determined individually rather than in the order of groups is set to be the largest at the intermediate position between the P range and the R range.

[0070] Specifically, at the P-R intermediate position, there are changes in the output pattern due to one sensor H2 switching on, subsequent changes in the output pattern due to one sensor H4 switching on, and subsequent changes in the output pattern due to one sensor H5 switching off. Therefore, the number of changes in the output pattern due to one sensor switching at the P-R intermediate position is three, related to sensors H2, H4, and H5. Similarly, at the R-N intermediate position, the number of changes in the output pattern due to one sensor switching is one, related to sensor H7. Also, at the N-D intermediate position, the number of changes in the output pattern due to one sensor switching is one, related to sensor H1. Further, at the D-M intermediate position, the number of changes in the output pattern due to one sensor switching is one, related to sensor H4.

[0071] In this way, sensors H1 to H8 are arranged so that in the event of a single failure where any one sensor fails, the failed sensor can be identified. Also, in the event of a single failure, the ECU20 determines the shift range based on the remaining sensors that have not failed.

[0072] The plurality of sensors H1 to H8 output a plurality of output patterns that do not overlap with the shift range and other intermediate positions at a plurality of intermediate positions between the plurality of shift ranges (lever positions), and are arranged such that the detection signals of the sensors change in a predetermined order as the select lever 11 moves through the intermediate positions between adjacent shift ranges.

[0073] During the process of the select lever 11 moving to the intermediate position, the detection signals of the sensors change in a predetermined order, so that the number of output patterns during normal operation can be reduced, and the number of output patterns that can be determined as an abnormality in the case of a single failure where one of the plurality of sensors H1 to H8 fails can be increased. For this reason, sensor abnormalities can be easily detected, and when an abnormality is determined, it is possible to determine which abnormal output pattern corresponds to by referring to an abnormality map that covers all output patterns during single failure. That is, in the present invention, when an abnormal output pattern is detected, the abnormality map is referred to and compared with the output pattern during single failure, and the selected shift range is estimated and the failed sensor (the sensor with abnormal output) can be identified. And since it is possible to suppress the output pattern during single failure from overlapping with the output pattern during normal operation, the number of shift ranges in which one failed sensor can be identified can be increased. Therefore, when any one of the plurality of sensors H1 to H8 fails, the failed sensor can be identified. Since it is a single failure and the failed sensor can be identified, in subsequent control, control can be continued based on the outputs of other sensors without using the output of the failed sensor. Incidentally, when referring to the abnormality map and comparing it with the output pattern during single failure, if there is no corresponding output pattern, there is a possibility of a multiple failure where a plurality of sensors have failed. When this abnormal output pattern continues and it is considered that a shift range is selected instead of the intermediate position, fail-safe control such as determining that it is a multiple failure and stopping the running is performed.

[0074] Also, the number of sensors H1 to H8 whose on and off are switched during the process of the select lever 11 moving through the intermediate position (D-M intermediate position) between the shift ranges constituting the forward driving range is less than the number of sensors H1 to H8 whose on and off are switched during the process of the select lever 11 moving through the intermediate position between the shift ranges constituting the non-forward driving range. The plurality of sensors H1 to H8 are arranged so that. Since the number of sensors that are turned on or off at the intermediate position between the forward driving ranges is small, the total number of sensors can be reduced.

[0075] As a result, during the process in which the select lever 11 moves to the intermediate position of the shift range switching related to the switching of the traveling direction, etc., where misjudgment of the shift position due to a failure of any one of the sensors H1 to H8 becomes a major problem, the number of sensors that switch between on and off is increased to suppress false detection, and the failed sensor can be surely identified.

[0076] That is, during the process in which the select lever 11 moves to the intermediate position of the range where misjudgment of the shift position due to a failure of any one of the sensors H1 to H8 becomes a major problem, since the number of sensors that switch between on and off is relatively large, the on or off state and the output pattern of the sensors change frequently in a short period of time, so the opportunity to identify the failed sensor can be increased.

[0077] Also, when a single failure occurs in which any one of the plurality of sensors H1 to H8 always outputs either on or off due to a failure, in at least one of the plurality of shift ranges, an abnormal output pattern does not overlap with the normal output pattern, so that the failed sensor can be identified, and the plurality of sensors H1 to H8 are arranged so that it is possible to identify whether the failed sensor is in an on-failure state where it always outputs on or an off-failure state where it always outputs off. That is, when a single failure occurs, since the abnormal output pattern output in at least one of the plurality of shift ranges matches the output pattern at the time of the single failure, the failed sensor can be identified.

[0078] As a result, when a single failure occurs, even if it is not possible to identify the failed sensor and whether it is in an on-failure or off-failure state at a single shift position because the abnormal output pattern overlaps with the normal output pattern, it can be identified at other shift positions, so that the failed sensor can be surely identified and whether it is in an on-failure or off-failure state can be identified. Note that even when a single failure occurs where the failed sensor as described above cannot be identified, the shift range can be identified.

[0079] Also, a plurality of sensors H1 to H8 are arranged such that the number of sensors capable of identifying a malfunction is greater in the non-neutral range than in the neutral range when a single failure occurs.

[0080] As a result, in the non-neutral ranges of the P range, R range, D range, and M range, which would pose a major problem if the shift position is misjudged due to a malfunction of any of the sensors H1 to H8, the number of sensors capable of determining a malfunction increases, and the chance of identifying the malfunctioning sensor can be increased.

[0081] Also, in the neutral range where it is less likely to cause a major problem even if the shift position is misjudged due to a malfunction of any of the sensors H1 to H8, the total number of sensors can be reduced by decreasing the number of sensors capable of determining a malfunction.

[0082] Also, the change in the detection signals of the sensors in a predetermined order includes a change caused by one sensor switching on or off and a change caused by a group of multiple sensors switching on or off in any order. And a plurality of sensors H1 to H8 are arranged such that the change in the detection signal caused by one sensor switching on or off is the largest at an intermediate position between the P range (parking range) and the R range (reverse range).

[0083] As a result, the amount of movement of the select lever 11 is relatively large, and at the intermediate position of the shift from the P range to the R range performed at the start of driving, the number of sensors related to the change in the output pattern in a predetermined order increases. Therefore, the number of normal output patterns can be reduced, and it becomes easier to detect abnormal output patterns.

[0084] When a single fault occurs in which the detection signal of any one of the plurality of sensors H1 to H8 becomes an abnormal value due to a fault, the ECU 20 identifies the faulty sensor by comparing it with a normal-time map that defines a normal output pattern consisting of detection signals with normal values. Then, the ECU 20 determines the shift range based on the detection signals of the remaining sensors among the plurality of sensors H1 to H8 and performs the first fail-safe. The first fail-safe is running in the shift range determined based on the detection signals of the remaining sensors excluding the faulty sensor. For example, when a single fault occurs during driving in the D range, the ECU 20 determines the D range based on the detection signals of the non-faulty sensors and continues driving in the D range. And when the select lever 11 is switched to, for example, the R range, the ECU 20 determines the switch to the R range and drives in the R range. Therefore, since a fail-safe that forcibly sets the N range does not occur due to the occurrence of a single fault, the driver can continue driving.

[0085] Here, the faults of the sensors H1 to H8 include transient faults caused by temporary noise or poor contact. When a transient fault occurs, it is desirable to return to normal (return to the normal state) with the elimination of the cause. In the control device of the present invention, it returns to normal (returns to the normal state) with the elimination of the fault.

[0086] During the execution of the first fail-safe, when the detection signal of the sensor identified as faulty by the ECU 20 of the control device of the present invention reverses from an abnormal value to a normal value and a predetermined time has elapsed since the reversal to the normal value, the first fail-safe is terminated and the normal control is resumed.

[0087] Specifically, when a single fault occurs in the sensors H1 to H8, the ECU 20 determines that the detection signal of the sensor identified as faulty (the sensor with a confirmed fault) has reversed from an abnormal value to a normal value due to the normalization of the sensor (the first condition), and any shift range determined by referring to the normal-time map has continued for a predetermined time (the second condition). When both conditions are satisfied, the first fail-safe is terminated and the normal control is resumed.

[0088] Further, when a multiple fault occurs in which detection signals of any two or more of the plurality of sensors H1 to H8 become abnormal values due to a fault, the ECU 20 performs a second fail-safe. The second fail-safe is control that permits traveling in the shift range determined before the fault and prohibits traveling after the vehicle stops. For example, when a multiple fault occurs during traveling in the D range, the ECU 20 permits traveling in the D range, which is the shift range determined before the fault. Then, when the HCU 20 detects that the vehicle speed has become 0 and the vehicle has stopped, it prohibits traveling. Note that this prohibition of traveling may be performed by switching the automatic transmission 4 to the N range or the P range. Further, during the execution of the second fail-safe, the ECU 20 notifies the driver of the occurrence of the multiple fault by the warning device 30.

[0089] With reference to the flowchart of FIG. 4, the operation of the ECU 20 will be described.

[0090] As shown in FIG. 4, the ECU 20 determines whether the sensors H1 to H8 are normal (step S1). Here, the ECU 20 determines that it is normal when all of the sensors H1 to H8 are normal, and determines that it is not normal when any of the sensors H1 to H8 is not normal. The determination as to whether the sensors H1 to H8 are normal is made based on whether the output pattern matches the output pattern that occurs at the shift range and the intermediate position when the output pattern is normal. That is, if the output pattern is the output pattern existing in the normal-time map, it is determined to be normal.

[0091] When the sensors H1 to H8 are normal (YES in step S1), the ECU 20 specifies the shift range (denoted as the shift position in the figure) with reference to the normal-time map (denoted as the normal map in the figure) (step S2), and ends the current operation.

[0092] When sensors H1 to H8 are not normal (NO in step S1), the ECU 20 determines whether it is a multiple fault (step S3). The determination of whether it is a multiple fault is made based on whether the detected abnormal output pattern matches the output pattern of the abnormal situation map that combines the output patterns in the case of single faults. That is, if the output pattern is not the output pattern existing in the abnormal situation map (output pattern in the case of single faults), it is determined as a multiple fault.

[0093] When it is a single fault rather than a multiple fault (NO in step S3), the ECU 20 excludes the failed switch, determines the shift range with the remaining switches (step S4), and ends the current operation.

[0094] When it is a multiple fault (YES in step S3), the ECU 20 continues control during running at the lever position at the time of fault occurrence (step S5) and ends the current operation. In step S5, when the ECU 20 stops running from running at the lever position at the time of fault occurrence (when the vehicle speed becomes 0 km / h), it is considered non-drivable.

[0095] Referring to FIGS. 5 and 6, the operation of the ECU 20 before and after the occurrence of a single fault in the sensors H1 to H8 will be described. In FIGS. 5 and 6, the item of order represents the passage of time, the item of actual fault state represents the actual fault state of the sensors H1 to H8, and the item of actual lever position represents the actual position (actual shift range) of the select lever 11 operated by the driver. Also, the item of determination position represents the shift range determined by the ECU 20, and the item of fault state represents the fault state of the sensors H1 to H8 determined by the ECU 20. Further, the item of reference map represents the type of map referred to by the ECU 20 for the determination of the shift range, the item of switch number (denoted as SW number in the figure) represents the on (1) or off (0) state of the detection signals of the eight sensors H1 to H8, and the item denoted as decimal represents the decimal value of the combination of the detection signals (the binary value obtained by arranging the detection signals). Here, the actual input value is the value of the actual detection signal input from the sensors H1 to H8 to the ECU 20, and the internal value for determination is the value used for the determination of the shift range. Also, the item of TM warning lamp in FIG. 5 represents the operating state of the warning device 30.

[0096] Referring to FIG. 5, the operation of the ECU 20 when a single fault occurs in the sensors H1 to H8 in the D range will be described.

[0097] In sequence 1, since all the sensors H1 to H8 are operating normally, the item of actual fault state is normal, and the item of actual lever position is the D range. Therefore, the item of fault state is normal, the item of reference map is the normal map, the item of determination position is the same D range as the actual lever position, and the item of TM warning lamp is off.

[0098] After that, in Sequence 2, since Sensor H4 fails in the mode of being stuck ON, the detection signal of Sensor H4 changes from the normal value of 0 to the abnormal value of 1, and the item of the actual state of the failure becomes the stuck ON of Sensor H4 (denoted as SW4 in the figure). The decimal value in this state is "51", and since "51" exists at the D-M intermediate position during normal operation, at this stage, it has not yet been determined by ECU20 that Sensor H4 has failed in the mode of being stuck ON. Therefore, the item of the failure state remains undetermined, the item of the reference map is the normal map, and the item of the determination position is the D range (recovery).

[0099] After that, when the state of "51" continues for a predetermined time (about several seconds), in Sequence 3, the actual input value of the detection signal of Sensor H4 (the value is 1) is different from the output pattern in each shift range of the normal operation map, and it is determined by ECU20 that Sensor H4 has failed in the mode of being stuck ON. Therefore, the item of the failure state is changed to failure determination, the item of the reference map is changed to the map for single failure of Sensor H4 (denoted as SW4 failure map), the detection signal of Sensor H4 can be either on (1) or off (0), and since the determination position determined from the detection signals of sensors other than Sensor H4 with reference to this SW4 failure map is the D range, the normal value of 0 is used as the internal value for determination and is used as the normal value of "35" for subsequent processing. In addition, along with the change of the failure state to failure determination, the TM warning light is lit. If the state of "51" is for a short time (several seconds), ECU20 does not determine that Sensor H4 has failed in the mode of being stuck ON, and normal control continues.

[0100] After the failure determination of sensor H4 is confirmed and the abnormal output of sensor H4 is temporary, in sequence 4, when the detection signal of sensor H4 changes from 1 (stuck - on failure) to 0 (normal), the item of the actual failure state becomes normal. In this sequence 4, the detection signal of sensor H4, for which the failure has been confirmed, reverses from the abnormal value of 1 to the normal value of 0 and becomes the output pattern of the D - range in the normal - time map. Also, the item of the determination position has the D - range continue for a predetermined time. For this reason, it is determined by ECU20 that normal recovery has occurred, the item of the failure state returns to normal, the item of the reference map returns to the normal map, and the TM warning light is turned off.

[0101] Referring to FIG. 6, the operation of ECU20 when a single failure occurs in sensors H1 - H8 in the P - range will be described.

[0102] In sequence 1, since all sensors H1 - H8 are operating normally, the item of the actual failure state is normal, and the item of the actual lever position is the P - range. For this reason, the item of the failure state is normal, the item of the reference map is the normal map, and the item of the determination position is the same P - range as the actual lever position.

[0103] Thereafter, in sequence 2, due to sensor H4 failing in a stuck - on mode, the detection signal of sensor H4 changes from the normal value of 0 to the abnormal value of 1, and the item of the actual failure state becomes the stuck - on state of sensor H4 (denoted as SW4 in the figure). The decimal value in this state is "156", and since this value of "156" does not exist in the normal - time output pattern, it is possible to immediately determine that sensor H4 is stuck - on. However, there is also the possibility of momentary abnormal values. At this stage where a predetermined time (about several seconds) has not elapsed, it has not yet been confirmed by ECU20 that sensor H4 has failed in a stuck - on mode. For this reason, the item of the failure state is before confirmation, the item of the reference map is the normal map, and the item of the determination position is the P - range.

[0104] After that, when the state of "156" continues for a predetermined time, in sequence 3, the actual input value of the detection signal of sensor H4 (the value is 1) is different from the output pattern in each shift range of the normal-time map, and the ECU20 determines that sensor H4 has failed in a mode of being stuck ON. For this reason, the item of the failure state is changed to failure confirmed, the item of the reference map is changed to the map for single failure of sensor H4 (referred to as the SW4 failure map), the detection signal of sensor H4 can be either on (1) or off (0), and since the determination position determined from the detection signals of sensors other than sensor H4 with reference to this SW4 failure map becomes the P range, the normal value of 0 is used as the internal value for determination and is used as the normal value of "140" for subsequent processing. Also, along with the change of the failure state to failure confirmed, the TM warning light is lit.

[0105] After that, in sequence 4, the actual lever position is changed to the R range by the driver's operation, and the determination position determined with reference to the SW4 failure map becomes the R range. The normal value of the output of sensor H4 in the R range is 1, but since the value of 0 at the time of failure confirmation is maintained as the internal value, it is prevented from misrecognizing the value 1 at the time of failure of sensor H4 as the normal value.

[0106] After that, in sequence 5, sensor H4 normalizes from a temporary stuck-ON failure, and the item of the actual state of the failure becomes normal. However, since the output from sensor H4 remains 1 and does not change, the control during failure continues.

[0107] After that, in sequence 6, the actual lever position is changed to the D range by the driver's operation, and the determination position determined with reference to the SW4 failure map becomes the D range. In this sequence 6, the detection signal of sensor H4, which had been failure confirmed, is inverted from the abnormal value of 1 to the normal value of 0, and coincides with the value of 0 as the internal value set at the time of failure confirmation. And since both the actual input value and the internal value match the normal value of "35" in the D range, it is possible to easily determine the inversion (return to normal) of the sensor that has detected a failure.

[0108] After that, at sequence 7, the item of the determination position is that the D range continues for a predetermined time. For this reason, it is determined by the ECU20 that the normal return has occurred, the item of the failure state returns to normal, and the item of the reference map returns to the normal map.

[0109] As described above, in this embodiment, when a single failure occurs in which the detection signal of any one of the plurality of sensors H1 to H8 becomes an abnormal value due to a failure, the ECU20 identifies the failed sensor by comparing it with a normal-time map that defines a normal output pattern consisting of a detection signal of a normal value, determines the shift range based on the detection signals of the remaining sensors of the plurality of sensors H1 to H8, and implements a first fail-safe that permits running in the determined shift range.

[0110] As a result, when a single failure occurs, after identifying the failed sensor, fail-safe driving can be continued in the shift range determined using the detection signals of the remaining normal sensors that are not failed. For this reason, it becomes possible to self-drive to the repair base, and the convenience can be improved. In addition, since the shift range is determined using the detection signals of the normal sensors that are not failed, it is also possible to switch between forward and reverse, and fail-safe driving can be performed safely. As a result, when any one of the plurality of sensors fails, fail-safe driving can be continued safely in the shift range determined by the sensors that are not failed.

[0111] Also, in this embodiment, during the implementation of the first fail-safe, when the detection signal of the sensor identified as failed reverses from an abnormal value to a normal value and a predetermined time has elapsed since the reversal to the normal value, the ECU20 ends the first fail-safe and returns to normal control.

[0112] As a result, when a single failure due to a transient failure of the sensor is resolved, the vehicle returns to normal control, so it is not necessary to transport the vehicle to a repair base or the like for a command input or the like to cancel the fail-safe mode and return to the normal control mode.

[0113] Also, in this embodiment, when a multiple fault occurs in which detection signals of any two or more sensors among the plurality of sensors H1 to H8 become abnormal values due to a fault, the ECU 20 permits running in the shift range determined before the fault and implements a second fail-safe that prohibits running after the vehicle stops. During the implementation of the second fail-safe, the occurrence of the multiple fault is notified to the driver.

[0114] As a result, in the case of a multiple fault in which a plurality of sensors fail, only running in the shift range determined before the fault is permitted, so that fail-safe running can be continued safely. Therefore, it is possible to prevent the vehicle from stopping on the road. Also, by prohibiting running after the vehicle stops, when the select lever 11 is operated after the vehicle stops, it is possible to prevent the shift range from being misjudged and the vehicle from moving backward or forward unintentionally. Further, by notifying the occurrence of the multiple fault, the driver can recognize the occurrence of the multiple fault.

[0115] Although embodiments of the present invention have been disclosed, it is obvious that those skilled in the art can make changes without departing from the scope of the present invention. It is intended that all such modifications and equivalents be included in the following claims.

Explanation of Reference Numerals

[0116] 11 Select lever 20 ECU (Control unit) H1 to H8 Sensors

Claims

1. A selector lever moved by a driver to select any one of a plurality of shift ranges arranged sequentially adjacent to each other, and a plurality of sensors arranged such that a detection signal that is on or off is output according to the position of the selector lever in the selected shift range, and output patterns consisting of combinations of on or off of the detection signal are different from each other in the plurality of shift ranges, and a control unit that determines the selected shift range based on the detection signal, wherein the vehicle control device comprises: the control unit is configured to: when a single failure occurs in which the detection signal of any one of the plurality of sensors becomes an abnormal value due to a failure, identify the failed sensor by comparing it with a normal-time map that defines a normal-time output pattern consisting of the detection signal of a normal value, determine the shift range based on the detection signals of the remaining sensors of the plurality of sensors, and perform a first fail-safe that permits driving in the determined shift range, the vehicle control device being characterized in that.

2. the control unit is configured to: during the execution of the first fail-safe, when the detection signal of the sensor identified as failed reverses from an abnormal value to a normal value and a predetermined time has elapsed since the reversal to the normal value, end the first fail-safe and return to normal control, the vehicle control device according to claim 1, characterized in that.

3. the control unit is configured to: when a multiple failure occurs in which the detection signals of two or more of the plurality of sensors become abnormal values due to a failure, perform a second fail-safe that permits driving in the shift range determined before the failure and prohibits driving after the vehicle stops, and during the execution of the second fail-safe, notify the driver of the occurrence of the multiple failure, the vehicle control device according to claim 1 or claim 2, characterized in that.

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