System and method for detection of degradation of vacuum brake booster sensor
View Patent ↗Systems and methods for detecting degradation of a sensor in a vacuum brake booster coupled to a manifold of an internal combustion engine include measuring an engine or vehicle operating parameter to detect operating or control conditions and detecting degradation of the sensor based on the engine or vehicle operating parameter. In one embodiment the operating parameter is a measured or estimated manifold pressure. A pressure drop across a check valve disposed between the brake booster and the intake manifold may also be considered.
1. A method for monitoring operability of a sensor in a vacuum brake booster coupled to a manifold of an internal combustion engine in a vehicle, the method comprising:
determining whether the vehicle has been driven sufficient to change vacuum brake booster pressure;
monitoring changes in vacuum brake booster pressure;
determining whether the changes in vacuum brake booster pressure exceed a predetermined amount; and
indicating in-range sensor degradation in response to said determination of whether the changes in vacuum brake booster pressure exceed the predetermined amount.
2. The method of claim 1 wherein said determining whether the vehicle has been driven further includes determining whether the vehicle has been driven over a predetermined speed after starting.
3. The method of claim 1 wherein said determining whether the vehicle has been driven further includes determining whether the vehicle has been driven more than a predetermined distance after starting.