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 P0703: Torque Converter / Brake Switch Circuit MalfunctionCircuit/System Description
The body control module (BCM) monitors the stop lamp switch mounted on the brake pedal. The BCM sends a GMLAN serial data message to the engine control module (ECM) indicating the status of the stop lamp switch.
Conditions for Running the DTC
The engine is ON.
Conditions for Setting the DTC
| • | The ECM receives an invalid brake pedal status GMLAN serial data message from the BCM. |
| • | This diagnostic runs continuously. |
Action Taken when the DTC Sets
DTC P0703 is a type C Store Only DTC.
Conditions for Clearing the MIL/DTC
DTC P0703 is a type C Store Only DTC.
Reference Information
Schematic Reference
Connector End View Reference
Electrical Information Reference
Circuit/System Testing
Important: Fix any Brake System related DTCs before using this diagnostic.
Note: This DTC may be stored as a history DTC without affecting the operation of the BCM. Do not replace the BCM if this DTC is stored only as a history DTC and is not retrieved as a current DTC.
Using a scan tool is DTC P0703 current in the ECM?
| ⇒ | If DTC P0703 is current in the ECM, replace the BCM. |
| ⇒ | If DTC P0703 is not current in the ECM, the system is OK. |
Repair Instructions
Perform the Diagnostic Repair Verification .
