Diesel PCM Input

Power Monitor
The Diesel Engine Power Monitor (DEPM) strategy resides in the Transmission Control Module located inside of the PCM. The function of the DEPM is to monitor engine rpm when there is no power demand from the APP sensor.

Under normal engine idle operation, the DEPM value must always be higher than engine rpm. In the event that rpm does increase to its calibrated idle speed value following completion of deceleration fuel shutoff, due to the injectors not turning off, the DEPM will disable crank and cam output signals, sent by the PCM to the FICMM. The FICMM input line informs the DEPM when the injectors are turned on and when the injectors are turned off. When the FICMM line is either shorted or open, the monitor strategy assumes that the fuel injectors are always turned on and sets a DTC.