C1722

CIRCUIT DESCRIPTION
The LR damper actuator is driven by the CVRSS control module via a method known as Pulse-Width Modulation (PWM). Battery voltage is PWMed (switched on and off) at a high frequency (2.0 kHz), thus, controlling the amount of current delivered to the actuator. By controlling the amount of current to the actuator, the CVRSS control module can then control the damping force in the damper. A higher level of damping force is achieved by providing correspondingly higher current levels, relating to higher percentages of PWM duty cycle.

The default damper state (with no battery voltage, and thus no current, provided to the attached actuator) is one that provides a minimum damping force.

CONDITIONS FOR SETTING THE DTC
The DTC is set when the CVRSS control module measures a feedback voltage lower than a preset value during two consecutive OFF-state damper diagnostic test procedures.

The DTC is set when the CVRSS control module performs a test procedure on each damper actuator approximately every 16 seconds. During this test procedure the damper actuator is briefly energized (ON-state test) and de-energized (OFF-state test). If, twice consecutively, the feedback voltage during the OFF-state test is inside the open circuit range, the corresponding DTC is set.

The DTC turns HISTORY when the CVRSS control module no longer senses an open circuit condition in either of the two actuator lines.

ACTION TAKEN WHEN THE DTC SETS
^ The LR damper actuator will be disabled by commanding 0 % PWM duty cycle. The LR corner of the vehicle will be soft.
^ The SERVICE RIDE CONTROL message will be displayed.

CONDITIONS FOR CLEARING THE MIL/DTC
^ Use the scan tool.
^ Use the On-Board diagnostic CLEAR RSS CODES feature.

TEST DESCRIPTION

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.

The number(s) below refer to the step number(s) on the diagnostic table.

2. This step checks for an open circuit condition in the actuator or the actuator pigtail.
3. This step checks for an open circuit condition in CKT 1114.
4. This step checks for an open circuit condition in CKT 1115.