Circuit Description

PCM contains chips called Output Driver Modules (ODM) that provide 7 switchable ground outputs for operating solenoids, relays, warming lights, and other devices. Each of these ground outputs has an internal fault line that feeds back to the PCM. When output is off, the output driver should receive 12 volts, fed to the solenoid driver, etc. When output is on, it should receive zero volts, since it is grounding the output. If it receives zero volts when output is off or 12 volts when output is on, it sets the fault line low.

DTC P1652 is used to monitor the fault line of the lift/dive output to the Road Sensing Suspension (RSS) module. The RSS module sends a 12 volt signal to the PCM connector C1 terminal No. 24. The PCM then grounds this circuit when vehicle is accelerating rapidly (lift) or braking hard (dive). The RSS module will then command the suspension to "firm", increasing controllability of vehicle during these conditions.