For 1990-2009 cars only
Diagnostic Instructions
| • | 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. |
DTC Descriptor
DTC C1255 00: Electronic Control Unit (ECU) PerformanceDTC C1256 00: Program Read Only Memory (ROM) Checksum Error
Circuit/System Description
The engine control module (ECM) receives a serial data message from the electronic brake control module (EBCM) is detecting an internal malfunction.
Conditions for Running the DTC
The ignition switch is in the ON position.
Conditions for Setting the DTC
An internal EBCM malfunction exists.
Action Taken When the DTC Sets
The MIL indicators turns ON.
Conditions for Clearing the DTC
| • | The condition for the DTC is no longer present. |
| • | The ECM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles. |
Reference Information
Schematic Reference
Antilock Brake System Schematics
Connector End View Reference
Antilock Brake System Connector End Views
Electrical Information Reference
Scan Tool Reference
Circuit/System Verification
Verify that DTC C0550 is not set in the EBCM.
| ⇒ | If DTC is set, refer to DTC C0550. |
