Method for operating a motor vehicle

Abstract

The invention relates to a method for operating a motor vehicle with a combustion engine, wherein a preheating measure (7) is carried out before the motor vehicle starts a journey (10) in order to reach an operating temperature for components of an exhaust gas aftertreatment system and / or for an oxygen sensor of the motor vehicle. In particular, in order to avoid unnecessary introduction of preheating measures, provision is made for the driver of the motor vehicle to actuate a signal transmitter (1) as a trigger for the preheating measure (7) in order to clearly inform in advance of the impending departure of the motor vehicle.

Description

Technical Field

[0001] The invention relates to a method for operating a motor vehicle having an internal combustion engine, wherein preheating measures are carried out before starting the internal combustion engine in order to reach an operating temperature of a lambda ray sensor and / or an exhaust gas aftertreatment system for the motor vehicle. Background Art

[0002] In order to reduce emissions, motor vehicles are equipped with exhaust gas aftertreatment systems. An important component of such exhaust gas aftertreatment systems is one or more catalytic converters, which usually require a certain temperature for their operation. For example, for the first reaction capacity, a conventional exhaust gas catalytic converter requires an operating temperature of about 300°C. In addition, the oxygen sensor of the motor vehicle requires a certain temperature, usually about 700°C, for its own operation, which measures the residual oxygen content in the exhaust gas and is responsible for setting the optimal air / fuel ratio. In order to reach these required operating temperatures as quickly as possible, so far, after the engine is started, for example, the catalytic converter heating inside the motor is implemented, when the catalytic converter is heated, the idling speed is increased and the ignition time is shifted back, so as to achieve an increase in the exhaust gas temperature in this way and thus achieve a sufficiently fast start of the exhaust gas aftertreatment system. In addition, in order to achieve the required temperature, it is known to blow in secondary air with the help of a secondary air pump, so as to increase the oxygen content in the exhaust gas and achieve a sufficient temperature rise in the exhaust gas in combination with the "rich" exhaust gas through the re-reaction of the excess fuel in the exhaust system, which also ensures the start of the exhaust gas aftertreatment system. In addition to these motor-internal measures, motor-external heating measures are also known. For example, electrical preheating of the exhaust system by means of an E-catalyst (electrically operated heating catalytic converter) and / or heating of the intake air and / or exhaust gas burners for increasing the exhaust gas temperature can be used for rapid startup of the exhaust gas aftertreatment system. The exhaust gas burners can also additionally perform a parking heating function.

[0003] Since the most accurate or optimal air-fuel ratio is also important for minimizing emissions, the rapid achievement of the operating temperature of the lambda y sensor used in motor vehicles is also a decisive factor for compliance with emission limit values. In order to achieve the temperatures of approximately 700° C. required for the lambda y sensor, electrical heating of the lambda y sensor is usually provided.

[0004] German laid-open patent application DE 10 2017 113 366 A1 describes an exhaust gas aftertreatment system in which electrical heating measures are provided before starting the combustion engine so that effective exhaust gas aftertreatment can be achieved even from the start of the combustion engine. For triggering the preheating measures, for example, a door contact switch, a sensor for seat occupancy or a seat belt lock sensor can be used as a signal transmitter. Summary of the invention

[0005] The invention provides a method for operating a motor vehicle with a combustion engine, wherein preheating measures are implemented before the motor vehicle starts to reach the operating temperature of components of an exhaust gas aftertreatment system and / or an oxygen sensor for the motor vehicle. According to the invention, it is provided that as a trigger for the preheating measures, a signal transmitter is actuated by the driver of the motor vehicle to clearly inform the motor vehicle of the upcoming departure in advance. This measure can avoid the unnecessary introduction of preheating measures. Based on this, preheating measures, in particular heating measures outside the motor by consuming the electrical energy available in the motor vehicle, are implemented before the motor vehicle starts. As is known, the electrical energy available in a motor vehicle is limited. Firstly, a minimum capacity must be maintained for the battery of the motor vehicle, in particular the battery's state of charge should not drop below 30%. Otherwise, a problem-free starting process and operation of the motor vehicle can no longer be guaranteed. Traditionally, this is a major problem for preheating measures inside the motor vehicle. If such unnecessary preheating measures are implemented and the motor vehicle is not actually started afterwards, the battery's state of charge will quickly drop below the required minimum capacity limit, so that the motor vehicle can no longer be operated as required. In order to solve this problem, the method described proposes that the driver actuates a signal transmitter, by means of which the driver explicitly, i.e. intentionally, informs in advance of the desire to depart. As a result, it is no longer possible for the driver to, for example, only briefly sit in the vehicle without actually wanting to depart, thereby triggering unnecessary heating measures. These heating measures themselves lead to a significant consumption of electrical energy if the motor vehicle does not subsequently depart. In particular, when such unnecessary preheating measures are repeated, the capacity of the electrical energy supply device can be exhausted very quickly. The proposed method avoids such unnecessary introduction of preheating measures by the driver explicitly informing in advance of the desire to depart.

[0006] In principle, the preheating measures may also include motor-internal preheating measures in addition to motor-external measures, ie, in particular electrical heating measures. The advantages of the proposed method, as described above, are particularly effective in conjunction with motor-external heating measures.

[0007] In a particularly preferred design of the method, it is provided that, when the driver wants to start the journey with the aid of a motor vehicle but has not previously notified the departure of the motor vehicle by operating the signal transmitter, the departure of the motor vehicle and / or the start of the motor vehicle are delayed as necessary so that appropriate preheating measures can be implemented during this period to reach the required operating temperature. As an alternative or supplementary solution, a power-constrained departure or a power-limited departure can be performed to minimize negative emission effects. During the delayed departure, it can be provided, for example, that the start of the motor is delayed so that preheating measures, especially electric preheating measures, outside the motor can be implemented. It can also be provided that, although the motor can be started, the actual departure is delayed. In this case, additional preheating measures inside the motor can then be taken if necessary.

[0008] The delay is preferably indicated to the driver by a warning signal or the like, for example acoustically or by a corresponding optical display. In this case, it is advantageous to also communicate to the driver that due to the lack of a previously announced desire to depart, preheating has unfortunately not been carried out, so that departure must be delayed in order to make up for the preheating measures. By means of such a reminder, the driver quickly learns that it is useful to explicitly announce the desire to depart in advance.

[0009] As a heating measure external to the engine, for example, resistance heating on a heating plate is conceivable. As a further, possibly additional measure, the operation of an exhaust gas burner can be used, for example, together with an electric secondary air pump, so that by injecting gasoline into the exhaust system and burning it quickly, components in the exhaust gas aftertreatment system can be heated. Furthermore, as a heating measure external to the engine, heating of the intake air, in particular electrical heating of the intake air, can be provided. In principle, other heating measures, such as microwave-based heating measures, are also conceivable.

[0010] Typically, the motor-external heating measures carried out in the sense of the proposed method are provided for generating sufficient operating temperatures for one or more components of an exhaust gas aftertreatment system of a motor vehicle, in particular for one or more catalytic converters. This can relate, for example, to an exhaust gas aftertreatment system of a gasoline engine, which can be preheated electrically, for example by means of an electrically operated heating catalytic converter. In this sense, motor-external heating measures can also be used for diesel engines in a corresponding manner, for example to preheat an oxidation catalytic converter, an SCR catalytic converter or a NOx storage catalytic converter. In addition, the motor-external heating measures can include electrical heating of a lambda sensor. After the motor is started, the motor-external heating measures can also be combined with motor-internal heating measures, also for example to further optimize the corresponding operating temperature in the exhaust gas aftertreatment system by exceeding the starting temperature of the exhaust gas aftertreatment system. As a motor-internal heating measure, for example, the ignition timing can be delayed in order to adjust the efficiency here, thereby also increasing the temperature in the exhaust system.

[0011] When using an exhaust gas burner as a preheating measure, it can also be used in the sense of a parking heater if it is coupled to the engine cooling circuit, for example, via an additional heat exchanger. In summary, the parking heater strategy provided can be coupled with a preheating of the exhaust system outside the engine. In particular, for preheated engines, raw emissions are generally improved, which results in a shorter preheating time outside the engine. Furthermore, the activation of the parking heater is another criterion that very reliably indicates that the driver can actually anticipate an upcoming departure when approaching the vehicle.

[0012] The signal transmitter provided for the proposed method can be implemented, for example, as an operating element at an operating device for a vehicle access control system. For example, a corresponding button or other element can be provided at a transponder of an electronic vehicle access control system, which is configured so that the desire to depart is clearly notified in advance by operating the button or element. In a similar manner, a button or other element can be provided, for example, at a key for a motor vehicle. In addition to operating a button or a corresponding element, for example, voice and / or gesture recognition can also be provided in order to clearly notify the desire to depart or the planned departure of the motor vehicle in advance. Voice and / or gesture recognition can also be implemented, for example, by a correspondingly equipped operating device for a vehicle access control system, wherein a camera function or a microphone function may be required for this purpose. In a particularly advantageous manner, the signal transmitter for notifying the upcoming departure in advance can be implemented by a mobile device with computer functions, that is, for example, by a smartphone, tablet computer or similar portable terminal device with corresponding connectivity. In this case, for example, a microphone and / or camera of the mobile device can be used to notify the planned departure in advance within the scope of the corresponding application by voice recognition or gesture recognition. However, it is also possible to explicitly inform the driver of the desire to depart in advance, for example by clicking on a corresponding area within a correspondingly configured application on the mobile device. It is also possible that the signal transmitter can be actuated directly on the motor vehicle via a correspondingly configured sensor system. For example, a correspondingly configured button can be provided on a door handle or elsewhere, with which the driver informs the driver of his desire to depart in advance.

[0013] In a preferred embodiment of the proposed method, it is provided that the state of the electrical energy available in the motor vehicle is included as a further criterion for triggering the preheating measure and / or the extent of the preheating measure. This means that in particular the charge state of the onboard battery or the state of the onboard electrical system is checked in order to be able to determine whether sufficient energy is available for the preheating measure, in particular for the preheating measure external to the motor. Furthermore, the extent of the preheating measure can also be made dependent on the available electrical energy.

[0014] It is also very advantageous to check whether preheating measures are needed before introducing preheating measures as another criterion. Important parameters in this regard are especially the external temperature and / or the motor temperature and / or the temperature in the exhaust gas aftertreatment system. If, for example, the external temperature is relatively high or, for example, the motor and the exhaust system are still hot, preheating measures are usually omitted. Preferably, as a criterion, it is possible to consider the situation that the ambient temperature, especially the motor temperature, and / or the temperature of the exhaust gas aftertreatment system, and / or the onboard power supply state are lower than a predefined threshold value. Based on this, the ambient temperature and / or the motor temperature and / or the temperature of the exhaust gas aftertreatment system, especially the temperature in the catalytic converter or the temperature in the area of ​​the catalytic converter, are used as important input parameters to determine whether there is a cold start and what the current temperature conditions for the cold start are. These temperature conditions are advantageously used to determine whether preheating measures are needed and how strong these preheating measures should be if necessary. In this regard, the onboard power supply state also plays an important role, especially when electric heating measures are planned. Depending on the current onboard electrical system state, which can be detected, for example, by means of SOC (State of Charge) or via I-Soll or the like, the energy available for the preheating measures can be ascertained so that the preheating measures can be adjusted accordingly.

[0015] Within the scope of the proposed method, in a preferred embodiment, the departure probability can be calculated, for example, especially if the temperature conditions are such that heating measures are actually required. It can then be determined on the basis of this departure probability whether it makes sense to introduce preheating measures. Possible input variables for calculating the departure probability can include, for example, date, time, weekday, GPS position, GPS position history, school holidays, smartphone data (e.g. driver identification), garage door sensors and the like. From this data, scenarios can be derived that make the possibility of departure more or less likely. This is particularly meaningful in situations such as the following, in which it is necessary to verify that the departure desire is clearly notified in advance by operating the signal transmitter, or in which no clear departure desire is conveyed, but nevertheless, for example, the driver is approaching the motor vehicle or the driver's approach to the motor vehicle is recognized.

[0016] As a preheating measure, electrical preheating of the exhaust gas aftertreatment system by means of an electrically operated heating catalytic converter and / or actuation of an exhaust gas burner is particularly suitable. However, other preheating measures can also be implemented within the scope of the proposed method as a supplement or alternative. The use of an exhaust gas burner has the particular advantage that it can also be used as an independently activatable parking heater.

[0017] In addition, in a preferred design of the method, it is provided that as long as the prescribed operating temperature of the components of the exhaust gas aftertreatment system and / or the oxygen sensor has not been reached by the implemented preheating measures, the departure of the motor vehicle is delayed. Therefore, in these cases, the stage with preheating measures can be extended to a certain extent. In this case, it can also be provided that the motor start is delayed, so that the preheating measures are only performed outside the motor and no harmful emissions are generated. It can also be provided that although the departure of the motor vehicle is delayed, the motor can still be started. In this case, the preheating stage can be performed in the form of a combination of preheating measures outside the motor and inside the motor until the prescribed operating temperature is reached. In this case, the delay and its cause are also pointed out to the driver of the motor vehicle in a targeted manner. Cold starts are reliably avoided by these measures, and excessive emissions are expected in cold starts. As an alternative or supplementary solution, it can be provided that a power-limited departure is performed when the prescribed temperature is not reached by the preheating measures. However, it is preferred to set another function to turn off or circumvent this delay or power limitation, so that a quick departure can still be forced in an emergency.

[0018] In another preferred embodiment of the method, the preheating measure is terminated if the vehicle has not departed within a predeterminable time interval despite explicit advance notification of the impending departure by the driver of the vehicle. This ensures that the preheating measure is not continued for too long in the event of a short-term change in the driver's plans or the desire to depart, thus avoiding unnecessary energy consumption.

[0019] The proposed method enables optimal exhaust gas aftertreatment immediately at the start of a driving cycle by means of the heating measures. In addition, the proposed method avoids unnecessary triggering of the proposed heating measures, which may be associated with high energy consumption and corresponding costs and disadvantages. In order to meet legal exhaust gas standards, a rapid start-up of the exhaust gas aftertreatment system and the resulting minimization of exhaust gas emissions must be demonstrated at the start of a driving cycle. For example, an external temperature of 20° C. and a maximum idling phase of 20 seconds before the start of the test cycle were applicable to earlier exhaust gas standards. Newer exhaust gas standards, in particular with the so-called RDE cycle (Real Drive Emission), place significantly higher requirements on emission limit values, so that sufficiently rapid start-up of the exhaust gas aftertreatment system can hardly be achieved by engine-internal measures alone. Under RDE conditions, in particular, a spontaneous cold start without an idling phase at an external temperature of -7° C. is considered a possible standard for which the emission limit values ​​must be observed. Therefore, due to the omission of the idling phase and the lower starting temperature, the engine-internal catalytic converter heating is far from sufficient to achieve the limit values. These stringent statutory requirements can be easily met by the proposed method including heating measures external to the motor.

[0020] In addition to the manipulation of the signal transmitter for the purpose of clearly notifying the planned departure in advance, other criteria can also be considered, which can be used in particular to verify the conveyed departure desire. If the departure desire cannot be verified by such criteria, the preheating measures started can be interrupted to avoid unnecessary energy consumption. Therefore, for example, the signal of the distance sensor of the motor vehicle can be evaluated, which is triggered according to the situation of a person entering the vehicle environment. These distance sensors thus show that the driver has entered the vehicle environment and is actually facing departure. According to the distance relative to the vehicle, different strategies can be followed in a hierarchical manner if necessary. In a similar manner, the signal from the optical and / or acoustic sensor device of the autonomous driving can be considered, which is triggered according to the situation of a person entering the vehicle surroundings. Accordingly, the near-field entrance of the transponder and its position relative to the vehicle can also be considered. In addition, for example, the door opening signal and / or the driver's seat recognition can be used as another criterion. In addition, the position of the mobile phone of the driver of the motor vehicle can be considered so that when the mobile phone approaches the motor vehicle, it is considered that the departure will actually be soon. In addition, for example, the user behavior of the driver of the motor vehicle can be derived from the data of the mobile phone. Thus, for example, it is possible to use the identification of the location of the driver's mobile phone, if necessary together with possible identification or learning and / or coupling of user behavior, for example from date, time and / or calendar information and the like, so as to be able to deduce from this the probability of whether the start of driving is actually imminent. In a similar manner, the location of a transponder-equipped document, such as a company document, of the driver of the motor vehicle can be evaluated. Once, for example, the entry of the document into the surroundings of the motor vehicle and thus the entry of the driver of the motor vehicle into the surroundings of the motor vehicle is identified, it is possible to implicitly infer that there is a high probability of actually imminent departure. These different criteria can be used as additional criteria to verify the departure desire that has been clearly communicated, and when the driver's plans change or when the desire to drive is incorrectly communicated, the triggered preheating measures can be terminated. The explained criteria can be evaluated individually or in different combinations.

[0021] As a further criterion for verifying the communicated departure request, information from the satellite-based positioning of the motor vehicle can be taken into account in conjunction with the definition of the motor vehicle's home position. In this embodiment, a scenario can be derived from this criterion and with the aid of the GPS position of the motor vehicle by defining a home position (vehicle-home position), which is obtained, for example, from the destination "Home" by determining it in the navigation system. Thus, for example, when a "not home position" is detected, the probability that a departure is actually intended is generally increased. Such a detection indicates, for example, a supermarket scenario, a service area scenario or the like, so that there is a high probability that a departure is actually imminent within a short period of time.

[0022] Furthermore, it can be provided that an explicitly expressed "desire not to depart" can also be communicated, for example, by means of a correspondingly configured key or button on the operating device of the vehicle access control system or by voice recognition or the like via a mobile phone. This makes it possible, for example, to cancel the previously expressed desire to depart again, so that the preheating measures introduced can be quickly terminated again in the event of a change of plans. Such an explicit advance notification of an unintentional departure can be very useful, for example, when a vehicle loading, service activity, visit to a repair shop or the like is planned. In a particularly preferred manner, for example, a "trunk compartment" button on the transponder of the electronic vehicle access control system can be provided for use in this sense. Furthermore, for example, a signal of a sensor device indicating that the trunk compartment of the motor vehicle is open or a "trunk compartment open / closed" sensor on the motor vehicle can be evaluated in a corresponding manner in order to indicate that there is no imminent engine start or departure, possibly contrary to the original advance notification given by the driver. Furthermore, a distance sensor on the motor vehicle can be used in a corresponding manner, which indicates that there is no intention to approach the driver's door, but, for example, an intention or an approach in the direction of the trunk compartment. Such a signal can also be evaluated as a negative criterion, from which it can be concluded that there is a certain probability that the original advance notice will be violated and that no subsequent motor start is imminent.

[0023] Preferably, the probability of departure and / or an estimate of the time available until the combustion engine can be expected to start or until departure is determined or implemented based on the evaluation of various criteria. On this basis, it is decided whether and, if necessary, to what extent heating measures external to the engine are to be implemented in order to ensure that the operating conditions for starting the exhaust gas aftertreatment system and / or the lambda hydride sensor are present at the required operating temperature with the start of the combustion engine. Preferably, when determining the heating measures external to the engine to be implemented, a calibration with the available electrical energy from the vehicle electrical system is performed. For this reason, excessive loading of the battery due to heating measures external to the engine should be avoided when the battery is only slightly charged, so as not to endanger the upcoming start of the engine.

[0024] In addition, the present invention includes an operating device for a vehicle access control system, which is distinguished by an operating element, by means of which the driver of the motor vehicle can clearly inform in advance of an upcoming or planned departure of the motor vehicle. The operating element can be, for example, a button or other element of the operating device that is configured accordingly. In addition, the operating element can also be, for example, a camera or a microphone, by means of which a corresponding voice recognition or gesture recognition can be performed, by which the driver of the motor vehicle can inform in advance of his departure desire. The operating device can be additionally designed so that the desire not to start driving can also be expressed by means of the operating device, which is achieved, for example, by operating another button or by multiple operations of a button provided for conveying the departure desire. Thus, for example, a previously conveyed departure desire can be revoked. The last operating device for conveying the desire not to depart can be, for example, a luggage compartment button that is usually provided, which is then provided accordingly.

[0025] The invention also includes an application for a mobile device with computer functions, wherein the application is set up as an operating means for a signal transmitter, which is operated by the driver of the motor vehicle in order to clearly inform the driver of an upcoming departure of the motor vehicle in advance. In this case, the application can be configured, for example, so that the desire to depart and, if necessary, also the desire not to depart can be communicated by pressing a button or by clicking on a corresponding area on the display of the mobile device. In other embodiments, the application can work, for example, with voice recognition or gesture recognition, so that the desire to depart (or not to depart) can be communicated very easily and intuitively.

[0026] The invention also includes a computer program configured to implement the steps of the proposed method. The invention also includes a machine-readable storage medium on which such a computer program is stored and an electronic control device configured to implement the steps of the proposed method. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Further features of the proposed method are apparent from the following description of exemplary embodiments in conjunction with the accompanying drawings. In this case, the individual features can be realized individually or in combination with one another.

[0028] In the attached picture:

[0029] Figure 1 A schematic flow chart showing a preferred embodiment of the proposed method with advance notification of a desire to start driving; and

[0030] Figure 2A schematic flow chart shows a preferred embodiment of the proposed method without prior notification of a desire to start driving. DETAILED DESCRIPTION

[0031] Figure 1An exemplary flow chart of the proposed method is shown. In step 1, the driver informs in advance of the desire to start driving, for example by actuating a correspondingly provided button on the transponder of the electronic vehicle access control system or by a voice command within the scope of a corresponding application on his smartphone. When the desire to start driving is communicated to the corresponding control device of the motor vehicle, in the following query 2, it is checked whether the corresponding temperature conditions, for example in terms of the external temperature, the temperature in the area of ​​the catalytic converter, etc., require preheating measures outside the motor. If this is not the case, the method is terminated in step 3 so that no preheating measures outside the motor are carried out, so that the start can be made without other heating measures. If the temperature conditions do require preheating measures outside the motor, then in query 4, it is checked whether the driver is actually approaching the vehicle. This can be done, for example, on the basis of a recognizable transponder movement with the aid of a distance sensor or other sensor device, for example from the environment of autonomous driving. In addition, the driver's trajectory on the way to the vehicle can be determined as possible. If it is detected in query 4 that the driver is not approaching the vehicle, the method can be interrupted without other preheating measures (step 3), because it can be assumed that the start was not made in violation of the driver's original plan. If the driver is approaching, then in step 5, the available time until the expected motor start and / or departure is estimated based on the criteria considered in query 2. Here, the prediction of the expected motor start time can be improved by adapting or modeling or training the corresponding model of driver behavior from the past process if necessary. According to the available time window, the necessary heating measures outside the motor are determined in step 6. This is also done in particular when calibrated with the available onboard power supply or battery state. In particular, it is determined here: when and with what power to start which heating measures. In step 7, the preheating phase is started accordingly with the heating measures outside the motor. After the motor starts 8, it is checked in query 9: whether the required temperature for the required harmful substance conversion, especially the catalytic light-off temperature (Kat-Light-Off-Temperatur), has been reached. The corresponding situation applies to the operating temperature of the oxygen sensor. If these temperature conditions are reached, the vehicle can be started in step 10. If the temperature conditions are not reached, the departure is delayed in step 11 or a power-limited departure can be performed. The delay of the start can be coupled to a further preheating measure in step 12, wherein the motor-external heating measure is combined with a motor-internal heating measure, for example with homogeneous split injection, with the setting of a later ignition angle or the like. Subsequently, a query 9 can be made again: whether the temperature conditions for the required pollutant conversion have been reached. If this is the case, the vehicle can be started 10.If a delay 11 occurs, the driver is warned in a targeted manner, for example by means of a visual or acoustic signal.

[0032] In the case of an urgent departure situation, it can be provided that the departure block or delay 11 is “overridden”. The number of such emergency departure situations can be incremented by a counter in the ECU (Engine Control Unit) and can be limited to a maximum number. The counter can then only be reset at a service station if necessary and recorded via the OBD (On-Board Diagnose) interface.

[0033] If the estimation of the time remaining until the expected engine start or departure carried out in step 5 leads to a prediction that the required temperature cannot be reached by means of engine-external and, if necessary, engine-internal heating measures, provision can be made to postpone the departure until the required functionality of the exhaust gas aftertreatment system is ensured. In this case, the delay is also pointed out to the driver in a targeted manner.

[0034] If, despite the driver's prior notification (step 1), the engine is not started within the expected time frame, it can be specifically provided that the engine-external heating measures are only carried out for a certain period of time, so that the preheating measures can be interrupted if no further journey is expected. This can be made dependent on other criteria, such as the temperature of the catalytic converter, the driver's seat detection ("is there anyone sitting in the vehicle at all?"), the temperature of the catalytic converter, the driver's seat detection ("is there anyone sitting in the vehicle ... preheating measures can be interrupted if the preheating measures are not expected. ”), a door closing signal and / or a signal of a near-field sensor device, the signal of which prompts the driver to leave the vehicle environment, for example, away from the transponder. In addition, the maintenance of the preheating phase can be made dependent on whether the state of the onboard power supply is sufficient.

[0035] In another scenario, the driver approaches the vehicle but does not express or communicate a clear desire to start driving. Figure 21 is shown as another exemplary embodiment for implementing the method. That is, when the driver approaches and does not express a desire to start driving (step 101), if driving is to be started without prior notification and unfavorable or possibly delayed cold starts are to be avoided for emission reasons, the following process can be executed. First, a query 102 is made as to whether the temperature conditions, such as the outside temperature and / or the temperature in the exhaust gas aftertreatment system, require preheating measures outside the engine. If this is not the case, the method can be stopped in step 103 and no heating measures are performed. If the temperature conditions require heating measures, the departure probability is calculated in step 104. Possible input variables in this case can be, for example, date, time, weekday, GPS position, GPS position history, school holidays, smartphone data (such as driver identification), garage door sensor and the like. Based on this data, a corresponding model can then be trained using a data mining method and / or the departure probability can be calculated on this basis. If query 105 indicates that the probability of departure is only very low, the method can be terminated with step 103, so that no further preheating measures are carried out, since departure is not expected. If query 105 indicates that the predicted probability of departure is high, then in step 106 the engine start and / or departure is delayed, so that during this time preheating measures can be carried out in step 7. The driver is informed of the delay and its cause by a suitable warning signal, for example acoustically or optically. The following steps correspond to the steps according to Figure 1 In this respect, reference is made to the corresponding description.

[0036] In summary, the proposed method and the measures described here allow: a spontaneous cold start is possible in accordance with legal emission requirements even without delayed start or can be guaranteed with only a minimal delay. If necessary, heating measures, in particular catalytic heating measures, inside the engine can be withdrawn, which furthermore allows advantages to be expected with regard to particle emissions.

Claims

1. A method for operating a motor vehicle with a combustion engine, wherein a preheating measure (7) is carried out before the motor vehicle starts traveling (10) in order to reach an operating temperature of components for an exhaust gas aftertreatment system and / or an oxygen sensor for the motor vehicle, characterized in that: Provision is made for the driver of the motor vehicle to actuate a signal transmitter (1) as a trigger for the preheating measure (7) in order to explicitly notify in advance of an impending departure of the motor vehicle, wherein when departure of the motor vehicle is requested, if necessary, the departure and / or engine start of the motor vehicle is delayed (106) without previous actuation of the signal transmitter by the driver, and during this time, the preheating measure (7) is implemented and / or a power-limited departure is performed.

2. The method according to claim 1, characterized in that As long as a prescribed operating temperature for components of the exhaust gas aftertreatment system and / or for the lambda yser has not yet been reached by the preheating measures, departure of the motor vehicle is delayed (11) and / or takes place with limited power.

3. The method according to claim 2, characterized in that A warning signal is generated as a reminder of the delay (106).

4. The method according to any one of claims 1 to 3, characterized in that The signal transmitter can be actuated via an operating element on an operating device for a vehicle access control system.

5. The method according to any one of claims 1 to 3, characterized in that The signal transmitter can be operated via a mobile device having computer functionality.

6. The method according to any one of claims 1 to 3, characterized in that The state of the electrical energy available in the motor vehicle is included as a further criterion for the scope and / or initiation of the preheating measures.

7. The method according to any one of claims 1 to 3, characterized in that Calculate the departure probability.

8. The method according to any one of claims 1 to 3, characterized in that The preheating measures include electrical preheating of the exhaust gas aftertreatment system by means of an electrically operated heating catalytic converter and / or the actuation of an exhaust gas burner.

9. The method according to any one of claims 1 to 3, characterized in that In the event that, despite explicit advance notification of an upcoming departure, the vehicle does not depart within a predeterminable time interval, the preheating measure is terminated.

10. The method according to claim 4, characterized in that The operating device has an operating element for explicit advance notification of an impending departure of the motor vehicle.

11. The method according to claim 10, characterized in that The operating device is a transponder of an electronic vehicle access control system or a key for a motor vehicle.

12. The method according to claim 5, characterized in that The signal transmitter can be operated via a smartphone or tablet.

13. An application product for a mobile device with computer functions, characterized in that: The application product is designed as an operating device for a signal transmitter, which is operated by the driver of the motor vehicle in order to explicitly inform the motor vehicle in advance of an upcoming departure, wherein when the departure of the motor vehicle is requested, if necessary, the departure and / or engine start of the motor vehicle is delayed (106) without previous operation of the signal transmitter by the driver, and preheating measures (7) are implemented during this period and / or a power-limited departure is performed. 14 . A computer program product configured to carry out the steps of the method according to claim 1 .

15. A machine-readable storage medium on which the computer program product according to claim 14 is stored. 16 . An electronic controller configured to carry out the steps of the method according to claim 1 .

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