C0665

Circuit Description
The Electronic Suspension Control Module monitors a lift/dive signal at the Powertrain Control Module (PCM). Under normal conditions, the Electronic Suspension Control Module supplies a 12 volt reference voltage to the PCM. The PCM grounds this circuit when the vehicle is accelerating rapidly (LIFT) or braking hard (DIVE). When the lift/dive signal goes low (approximately 0 volts), the Electronic Suspension Control Module commands all four Electronic Suspension Control dampers to a FIRM condition.

Conditions for Running the DTC
^ The ignition is on.
^ The fault is detected during three consecutive ignition cycles, or during the same ignition cycle after clearing the DTC using the scan tool.

Conditions for Setting the DTC
The DTC is set when the Electronic Suspension Control Module does not sense the low-to-high transition on the lift/dive circuit within 31 seconds after the ignition is turned ON.

Action Taken When the DTC Sets
^ The Electronic Suspension Control lift/dive function will be disabled.
^ The vehicle will pitch more during a braking or wide open throttle condition.
^ The SERVICE RIDE CONTROL message will be displayed.

Conditions for Clearing the MIL/DTC
^ The scan tool can be used to clear the DTC.
^ The On-Board diagnostics CLEAR RSS CODES feature can be used to clear the DTC.
^ The DTC is saved as history when the Electronic Suspension Control Module no longer sees the low-to-high transition on the lift/dive signal from the PCM during a valid test period. The DTC will clear if the fault does not return after 50 consecutive ignition cycles.

Diagnostic Aids
As part of the vehicle diagnostic system, the PCM toggles the lift/dive line within 31 seconds after the ignition is turned ON. This allows the Electronic Suspension Control Module to determine if the line is faulted or not. A retry is attempted every four minutes until successful.
An intermittent short to ground or an open circuit in the Lift/Dive Signal may cause a random firm/soft ride condition. Refer to Testing for Intermittent and Poor Connections in Wiring Systems.

Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
2. This step tests for the normal function of the PCM (inactive).
3. This step tests for the normal function of the PCM (active).






DTC C0665 Chassis Pitch Signal Circuit