C0665

DTC C0665





Circuit Description
The Continuously Variable Road Sensing Suspension (CVRSS) module monitors a lift/dive signal at the Powertrain Control Module (PCM). Under normal conditions, the CVRSS module supplies a 5 volt reference voltage to the PCM. The PCM grounds this circuit when the vehicle is accelerating rapidly or braking hard. When the lift/dive signal goes low to approximately 0 volts, the CVRSS module commands all four CVRSS dampers to a FIRM condition.

Conditions for Running the DTC
The ignition is ON.

Conditions for Setting the DTC
^ The DTC is set if the CVRSS module does not detect the low-to-high transition on the lift/dive circuit within 31 seconds after the ignition is turned ON.
^ The fault is detected during three consecutive ignition cycles, or during the same ignition cycle after clearing the DTC with a scan tool.

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

Conditions for Clearing the MIL/DTC
^ The scan tool can be used to clear the DTC.
^ The DTC is saved as history when the CVRSS module 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 CVRSS 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 in the Lift/dive Signal circuit may cause a random firm/soft ride condition.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
2. This step tests for proper voltage in the chassis pitch signal circuit.
3. This step tests for proper communication between the PCM and the CVRSS module.