P0703

DTC P0703












Circuit Description with 4L30-E Automatic Transmission
The brake switch receives battery voltage from the HAZARD fuse (fuse 12). The brake switch opens when the brakes are applied and closes when the brakes are released. The Engine Control Module (ECM) receives the brake switch signal on terminal 27 of connector C2. The ECM sends the brake switch status information to the Transmission Control Module (TCM) on a communication network called the Controller Area Network (CAN). A fault in the CAN will not cause DTC P0703 to set by itself. If a CAN fault occurs, other DTCs will set before DTC P0703.
When the TCM detects that the brakes have been applied while transmission output speed is detected for a specified amount of time, DTC P0703 sets. DTC P0703 is a type C DTC.

Condition for Running the DTC
Transmission output speed is greater than 192 RPM.

Condition For Setting The DTC
The TCM detects that the brakes have been continuously applied for 20 minutes.

Action Taken When the DTC Sets
^ The TCM does not request the ECM to illuminate the MIL.
^ The ECM records the operating conditions when the Conditions for Setting the DTC are met. The ECM records this information as Failure Records.
^ The TCM stores DTC P0703 in TCM history.

Conditions for Clearing the MIL/DTC
^ A scan tool can clear the DTC.
^ The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without a non-emission-related diagnostic fault occurring.

Diagnostic Aids
^ Inspect the brake switch for proper adjustment.
^ Inspect the TOM DTC history for DTC U2105 or U2100.

Test Description
The numbers below refer to the step number on the diagnostic table.
8. The TCC Brake Switch should be open when the brake pedal is applied.