DTC U1064: Loss Of BCM Communication: Testing
- If instrument cluster diagnostic system check was performed, go to next step. If instrument cluster diagnostic system check was not performed, go to INSTRUMENT CLUSTER DIAGNOSTIC SYSTEM CHECK under SYSTEM TESTS.
- Connect scan tool. Turn ignition switch to RUN position. Using scan tool, establish communication with BCM. If communication can be established, go to step 9 . If communication cannot be established, go to next step.
- Using scan tool, establish communication with other modules on class 2 serial data line. If communication can be established, go to next step. If communication cannot be established, go to SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DATA LINE .
- Check for poor connection at BCM Pink 24-pin harness connector C2, terminal B5 (Light Green wire). Repair as necessary and go to step 9 . If circuit is okay, go to next step.
- Disconnect BCM connector C2. Disconnect splice pack SP205 connector. See COMPONENT LOCATIONS . Using DVOM, check resistance between splice pack SP205 connector terminal "M" (Light Green wire) and BCM harness connector C2, terminal B5 (Light Green wire). See Figure . If resistance is 0-3 ohms, go to next step. If resistance is not 0-3 ohms, go to step 7 .
- Check resistance between BCM harness connector C2, terminal B5 (Light Green wire) and ground. See Figure . If resistance is 0-3 ohms, go to next step. If resistance is not 0-3 ohms, go to step 8 .
- Repair open or short to ground in appropriate circuit. See WIRING DIAGRAMS . Go to step 9 .
- Turn ignition switch to OFF position. Replace BCM. See appropriate BODY CONTROL MODULES article. Go to next step.
- Turn ignition switch to OFF position. Reconnect all connectors and components. Using scan tool, clear DTCs. Recheck system operation.