DTC U1040: Loss Of Communications With Abs: Testing
- If data link communications diagnostic system check has been performed, go to next step. If data link communications diagnostic system check has not been performed, perform data link communications diagnostic system check. See DATA LINK COMMUNICATIONS DIAGNOSTIC SYSTEM CHECK under SYSTEM TESTS.
- Using scan tool, attempt to establish communications with EBTCM. If scan tool communicates with EBTCM, go to next step. If scan tool does not communicate with EBTCM, diagnose brake system. See appropriate ANTI-LOCK article in BRAKES.
- Check and repair class 2 serial data line circuit No. 1807 (Purple wire) for intermittent conditions. See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS. After repairs, go to next step.
- Turn ignition switch to OFF position. Reconnect components and connectors. Turn ignition switch to ON position. Using scan tool, clear DTCs. After clearing DTCs, perform DATA LINK COMMUNICATIONS DIAGNOSTIC SYSTEM CHECK under SYSTEM TESTS.