TRAC Inoperative

CAUTION: If Anti-Lock Brake System/Traction Control Electronic Control Unit (ABS/TRAC ECU) replacement is necessary during testing, always ensure ABS/TRAC ECU connectors and ground circuit are okay. If either is suspect, repair and repeat testing to confirm ABS/TRAC ECU malfunction.

Retrieve Diagnostic Trouble Codes (DTC). Go to appropriate DTC for diagnostic procedure. Check IG power source circuit. See DTC 41: IG POWER SUPPLY CIRCUIT under DIAGNOSTIC TESTS. Check hydraulic system for leakage. Check speed sensor circuit. Perform appropriate wheel speed sensor circuit test. See DIAGNOSTIC TROUBLE CODE IDENTIFICATION table under DIAGNOSIS & TESTING. If all preceding tests are okay, replace ABS/TRAC ECU.