C1658

CIRCUIT DESCRIPTION
The Continuously Variable Road Sensing Suspension (CVRSS) control module performs checks of internal calibration data. If a fault condition is detected, the CVRSS control module will set the fault DTC, and may, depending upon the fault type, turn on the SERVICE RIDE CONTROL message. Additionally depending upon the type of the internal fault, the system will either enter a Speed Dependent Damping mode or disable all dampers. In the latter case, a message will be sent to the PCM to cause the vehicle speed to be limited. Recovery from any controller fault condition is attempted only after the ignition is cycled ON and OFF.

CONDITIONS FOR SETTING THE DTC
The Diagnostic Trouble Code (DTC) is set when any calibration faults, internal to the CVRSS controller, are detected. The DTC turns HISTORY when the CVRSS control module no longer senses the hardware fault and the ignition is cycled OFF and ON.

ACTION TAKEN WHEN THE DTC SETS
Depending upon which of the internal functions are affected by the fault condition, the CVRSS control module will take one of two sets of actions:
^ If the fault condition allows continued output operation, the system will enter a Speed Dependent Damping mode, in which all four corners of the vehicle are concurrently driven by a fixed Pulse Width Modulated (PWM) duty cycle, which increases as a function of the vehicle speed.
^ If the fault is more severe, the control module will disable ALL dampers by commanding 0 % PWM duty cycle, disabling the damper switched battery circuit, and sending a message to the Powertrain Control Module (PCM) to limit vehicle speed.

TEST DESCRIPTION
The number(s) below refer to the step number(s) on the diagnostic table.
1. This step checks to see if the problem has cleared after the CVRSS control module has been calibrated.
2. This step checks to see if the problem has cleared after the CVRSS control module has been calibrated.

IMPORTANT:
^ Do not backprobe the sensors, actuators, or any sealed connectors.
^ When all the diagnostics and repairs are complete, clear the DTCs and verify the operation.