Rear Wheel Steering Diagnosis

DTC C0550

Circuit Description

When the ignition switch is turned ON, the rear wheel steering control module monitors communications between its internal microprocessors and performs self-diagnostic tests. If an internal malfunction is detected, the rear wheel steering control module will store a DTC C0550 in its memory.

Conditions for Running the DTC

- Turn the ignition switch to the ON position, with engine ON.

Conditions for Setting the DTC

- The rear wheel steering control module detected an internal malfunction.
- The malfunction must be detected when the ignition switch is first turned ON.

Action Taken When the DTC Sets

- The Service 4-Wheel Steer indicator in IPC will be displayed.
- The code is displayed on scan the tool as DTC C0550.
- The output command to the motor is zeroed. The motor drive circuits are disabled using commands from the rear wheel steering control module to open the power relay.
- The rear wheels will be returned to the default centered position.

Conditions for Clearing the DTC

- Conditions for the DTC are not currently present.
- The module receives a clear code command from the scan tool.
- The DTC clears after 100 malfunction free ignition cycles.

Diagnostic Aids

- Any additional codes displayed with DTC C0550 should be diagnosed and repaired first.
- The rear wheel steering control module tests for multiple internal malfunctions and will store a DTC C0550 if one or more internal malfunctions are detected. Therefore, depending on which malfunction was detected, and what internal circuitry was affected, this DTC may cause various symptoms.
- Any condition resulting in the sensor supply voltage being pulled high or low could result in an erroneous DTC C0550.
- A fault in the battery positive voltage circuit from the 125A MEGA fuse can result in an erroneous DTC C0550.