C1278

CIRCUIT DESCRIPTION
When the EBTCM detects excessive wheel spin, the EBTCM will request that the PCM reduce engine torque via a high speed Pulse Width Modulated (PWM) signal on CKT 463.

CONDITIONS FOR SETTING THE DTC
The DTC C1278 sets when the EBTCM receives a communication failure data message from the PCM.

The DTC C1278 sets under the two following conditions:
^ EBTCM to PCM communications. CKT 463 or CKT 800 is open or shorted
^ PCM driveability conditions that would set PCM DTCs. If PCM DTCs are present, the malfunction may not exist with the ABS/TCS system.

ACTION TAKEN WITH THE DTC SETS
The following actions are taken when the DTC sets:
^ A malfunction DTC is stored
^ The TCS is disabled
^ The TRACTION OFF indicator lamp is turned ON

CONDITIONS FOR CLEARING THE DTC
The DTC will be cleared under following conditions:
^ Conditions for the malfunction are no longer present. Use the scan tool clear DTCs function.
^ 100 ignition switch key cycles have passed with no malfunctions detected

DIAGNOSTIC AIDS
Perform a thorough inspection of the wiring and the connectors.

Failure to carefully inspect wiring may result in misdiagnosis. A misdiagnosis may result in part replacement with reappearance of the malfunction.

Thoroughly inspect the following grounds:
^ G101
^ G102
^ G106
^ G110

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Part 2 Of 2:

DTC C1278 REQUESTED TORQUE SIGNAL CIRCUIT MALFUNCTION