DTC C0691: Damper Control Relay Circuit Range (Open Or Short To Ground)

Shock absorber solenoid voltage is supplied to RTD module through the RTD relay circuit. RTD module controls the operation of the RTD relay by grounding the relay control circuit. This closes relay contacts providing each shock absorber solenoid with supply voltage through RTD module's internal solenoid supply circuitry. Individual solenoid controls operation of corresponding shock absorber. The RTD module monitors the RTD relay control/solenoid voltage circuits to determine if the circuits are functioning properly. DTC C0691 will be set when the RTD detects low voltage (an open or short to ground) on relay solenoid control circuit. RTD module will disable all 4 solenoids (giving a soft ride), send a request to IPC to display SERVICE RIDE CONTROL and SHOCKS INOPERATIVE messages, and send a message to the PCM to limit vehicle speed to 80 MPH.

1. Perform RTD diagnostic system check. See RTD DIAGNOSTIC SYSTEM CHECK  under DIAGNOSIS & TESTING. After performing RTD diagnostic system check, go to next step.
2. Turn ignition off. Disconnect RTD relay. Turn ignition on. Connect test light between ground and Orange wire terminal of relay connector. See WIRING DIAGRAMS  . If test light illuminates, go to next step. If test light does not illuminate, go to step  9 .
3. Connect test light between Dark Blue and Orange wires of RTD relay. See WIRING DIAGRAMS  . Turn ignition on and off. If test light turns on and off when ignition is cycled, go to step  7 . If test light does not turn on and off, go to next step.
4. If test light remains illuminated when ignition is turned on and off, go to step  6 . If not, go to next step.
5. Check Dark Blue wire of RTD relay for an open. See WIRING DIAGRAMS  . If open is present, repair and go to step  12 . If open is not present, go to step  8 .
6. Check Dark Blue wire of RTD relay for short to ground. See WIRING DIAGRAMS  . If a short to ground is present, repair and go to step  12 . If short is not present, go to step  8 .
7. Check RTD relay circuit for poor connection or intermittent short. See NOTES ON INTERMITTENTS  under DIAGNOSIS & TESTING. See WIRING DIAGRAMS  . After repairs, go to step  12 . If poor connection is not present, go to step  10 .
8. Check for poor connection at harness connector of RTD module. If poor connection is present, repair and go to step  12 . If poor connection is not present, go to step  11 .
9. Repair Orange wire of RTD relay. See WIRING DIAGRAMS  . After repairs, go to step  12 .
10. Replace RTD relay. After repairs, go to step  12 .
11. Replace RTD control module. See RTD CONTROL MODULE  under REMOVAL & INSTALLATION. After repairs, go to next step.
12. Turn ignition off. Reconnect all disconnected components and connectors. Using scan tool, clear all DTCs. Operate vehicle. Repeat self test. If DTC resets, go to step  2 . If DTCs do not reset, system is okay.