Abs Does Not Operate

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

Retrieve Diagnostic Trouble Codes (DTC). See DIAGNOSTIC TROUBLE CODE IDENTIFICATION under DIAGNOSIS & TESTING. If any DTCs are present, perform appropriate diagnostic test. If no DTCs are present, check IG power source circuit. See DTC 41: IG POWER SUPPLY CIRCUIT under DIAGNOSTIC TESTS. Check speed sensor circuits. See DIAGNOSTIC TROUBLE CODE IDENTIFICATION table under DIAGNOSIS & TESTING. Check ABS actuator. See ABS ACTUATOR CHECK under COMPONENT TESTS. If ABS actuator is not okay, check hydraulic system for leakage. If all preceding tests are okay and ABS still does not operate, replace ABS ECU.