Circuit Description

PCM contains chips called the Output Driver Modules (ODM) that provide 7 switchable ground outputs for operating solenoids, relays, warning lights, and other devices. Each of these ground outputs has an internal fault line that feed back to the PCM. When the output is off, the output driver should receive 12 volts fed to the solenoids, relays, etc. When the output is on, it should receive zero volts, since it is grounding the output. If it receives zero volts when the output is off or 12 volts when the 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 lift/dive signal output in the PCM. The PCM then ground this circuit when the vehicle is accelerating rapidly (lift) or braking hard (dive). The RSS module will then command the suspension to "Firm" to increase controllability of vehicle during these conditions.