• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Left Front Damper Control Circuit | C0575 02 | C0575 04 | C0575 01 | -- |
Left Front Damper Low Reference Circuit | C0575 02 | C0575 04 | C0575 01 | -- |
Right Front Damper Control Circuit | C0580 02 | C0585 04 | C0580 01 | -- |
Right Front Damper Low Reference Circuit | C0580 02 | C0585 04 | C0580 01 | -- |
Left Rear Damper Control Circuit | C0585 02 | C0585 04 | C0585 01 | -- |
Left Rear Damper Low Reference Circuit | C0585 02 | C0585 04 | C0585 01 | -- |
Right Rear Damper Control Circuit | C0590 02 | C0590 04 | C0590 01 | -- |
Right Rear Damper Control Circuit | C0590 02 | C0590 04 | C0590 01 | -- |
The electronic suspension control module (ESCM) commands the damper solenoid ON and OFF. When the solenoid is initially energized, the supply voltage is then pulse width modulated (PWM). The amount the solenoid is activated is based on inputs from the driver tow/haul switch, road inputs, position sensor inputs, and the powertrain control module (PCM). The ESCM continuously compares each dampers command state with the state of their feedback circuits to ensure they agree.
The ignition is in the RUN position for 30 seconds.
• | Upon detection of the damper solenoid or the circuits to the solenoid are shorted to voltage when at 0-91 percent PWM. |
• | Allow 30 seconds for redetection after clearing codes. |
• | Upon detection of the damper solenoid or the circuits to the solenoid are shorted to ground when at 5-100 percent PWM for 3 consecutive ignition RUN cycles. |
• | Cycle the dampers for 30 seconds after clearing codes. |
• | The damper solenoid or the circuits to the solenoid are open when at 0-91 percent PWM for 3 consecutive ignition RUN cycles. |
• | Command the damper to the OFF state for 30 seconds after clearing codes. |
• | The DTC is stored in memory. |
• | The driver information center (DIC) displays the SERVICE SUSPENSION SYSTEM and SPEED LIMITED message. |
• | All dampers are disabled. |
• | The suspect damper is disabled. |
• | The DIC displays the SERVICE SUSPENSION SYSTEM. |
• | If any combination of 2 damper acutators short to ground or open circuit failures are simultaneously present, SPEED LIMITED will also be displayed in the DIC. |
Before proceeding with the diagnostics, ensure the electrical harness connector at the suspect damper is fully engaged by pushing the harness connector toward the damper. If an audible click is heard, or substantial engagement travel is noted, ensure the remaining damper connectors are fully engaged as well.
Electronic Suspension Control Schematics
Electronic Suspension Control Connector End Views
Electronic Suspension Control Description and Operation
Engine running, command the suspect damper solenoid On and Off with a scan tool while jouncing the suspension, verify an increase, and decrease in damping.
⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. |
3.1. | Connect a test lamp between the control circuit terminal A and the low reference circuit terminal B. |
3.2. | Ignition ON, with a scan tool, clear all ESC module DTCs. |
⇒ | If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the ESC module. |
⇒ | If the test lamp is always OFF, test for a short to ground or an open/high resistance on the control circuit. If the circuit tests normal, replace the ESC module. |
⇒ | If not within the specified range, replace damper. |
• | Control Module References for ESCM replacement, setup, and programming |