Torque Monitor
The torque monitor resides within the powertrain control module (PCM) as both software and as a redundant safety processor. The torque monitor detects certain computer faults of the PCM. The torque monitor also detects if the overall powertrain torque delivered to the output shafts of the vehicle is excessive to what the driver is requesting. The torque monitor detects 3 gross errors that are present for some calibrated amount of time:
- unintended vehicle motion - the powertrain accelerates the vehicle when it should not (such as in NEUTRAL) or provides torque in the wrong direction.
- excess acceleration - vehicle accelerates at greater rate than the driver or the speed control requests.
- excess powertrain deceleration - vehicle powertrain braking exceeds driver demand.
When any of the gross errors are detected, the torque monitor communicates it to the PCM, which initiates appropriate action such as limited operating strategy (LOS) mode. The torque monitor requested LOS mode can be cleared when the malfunction is not present anymore, and the key is cycled to the OFF position for about 10 seconds.