Method for monitoring a subsystem installed in a motor vehicle

Abstract

The invention relates to a method for monitoring a subsystem installed in a motor vehicle, in which a diagnostic unit checks the subsystem for system faults at least during driving cycles of the motor vehicle, wherein the check is carried out both for occurrence and for rectification of a system fault. The invention provides for the diagnostic unit to carry out a misuse estimation on the basis of a frequency with which the occurrence and / or the rectification of the system fault has / have been detected in order to determine whether the detected occurrence and / or the detected rectification of the system fault is / are based on misuse. If occurrence of the system fault is detected, a restriction operating mode is activated or an activated restriction operating mode is continued, in which mode drivability of the vehicle is restricted after a predefinable number of driving cycles have passed or after a predefinable travel distance has passed without the rectification of the system fault being detected.

Description

technical field

[0001] The invention relates to a method for monitoring subsystems installed in a motor vehicle according to the preamble of claim 1 . Background technique

[0002] Subsystems installed in motor vehicles, such as coolant systems, lubricant systems, passenger seat belt retractor systems, or other safety systems, are typically monitored for proper function or system errors. System errors are typically displayed to the driver of the motor vehicle and the driver is asked to correct the error.

[0003] Thus, for example, DE 195 48 684 A1 describes a method in which an exhaust-related error function occurring in a motor vehicle with an internal combustion engine is detected via an on-board sensor system and the error is recorded, And it is evaluated in the circuit unit and displayed by indicator lights if necessary.

[0004] For legal or liability reasons, it is necessary to ensure that system errors are eliminated when some errors occur. This also applies to ca...