For 1990-2009 cars only
DTC Descriptor
DTC C0550 31: Electronic Control Unit (ECU) Performance. - General Checksum FailureDTC C0550 32: Electronic Control Unit (ECU) Performance. - General Memory Failure
DTC C0550 38: Electronic Control Unit (ECU) Performance. - Supervision Software Failure
DTC C0550 39: Electronic Control Unit (ECU) Performance. - Internal Electronic Failure/Discard
Diagnostic Fault Information
Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
Circuit/System Description
When the ignition is turned ON, the electronic suspension control (ESC) module monitors communications between its internal microprocessors and performs self-diagnostic tests. If an internal malfunction is detected, the ESC module will store a DTC C0550 in its memory.
Conditions for Running the DTC
Ignition ON.
Conditions for Setting the DTC
| • | The ESC 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 ESC module disables all ESC functionality. |
| • | The ESC module disables all ESC functionality a message to the instrument panel cluster (IPC) to display the SERVICE SUSPENSION SYSTEM message |
Conditions for Clearing the DTC
| • | Under all fault conditions, the ignition must be cycled before this DTC can be changed from current to history. |
| • | The ESC module no longer detects any internal malfunctions when the ignition is first turned to the ON position. |
| • | A history DTC will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present. |
Reference Information
Schematic Reference
Suspension Controls Schematics
Connector End View Reference
Suspension Controls Connector End Views
Description and Operation
Electronic Suspension Control Description and Operation
Electrical Information Reference
Scan Tool Reference
Circuit/System Verification
Verify that DTC C0550 is not set
| ⇒ | If the DTC, is set replace the ESC. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for ESC replacement, setup, and programming.
