P1655

DTC P1655: Problem in TCM-to-ECM Communication Lines

NOTE:
^ Record all freeze data and review General Troubleshooting Information before you troubleshoot.
^ This code is caused by an electrical circuit problem and cannot be caused by a mechanical problem in the transmission.

1. Turn the ignition switch OFF.
2. Disconnect TCM connector B (22P) and ECM connector C (31P).





3. Check for continuity between TCM connector terminal B7 and ECM connector terminal C15.
Is there continuity?
YES- Go to step 4.
NO- Repair open in the wire between TCM connector terminal B7 and ECM connector terminal C15





4. Check for continuity between TCM connector terminal B7 and body ground, or between ECM connector terminal C15 and body ground.
Is there continuity?
YES- Repair short to ground in the wire between TCM connector terminal B7, ECM connector terminal C15 terminal, and body ground.
NO- Go to step 5.
5. Connect TCM connector B (22P).
6. Turn the ignition switch ON (II).





7. Measure the voltage between ECM connector terminal C15 and body ground.
Is there about 10 V?
YES- Go to step 8.
NO- Check for loose terminal fit in the TCM connectors. If necessary, substitute a known-good TCM, then recheck. If the symptom/indication goes away with a known-good TCM, replace the original TCM.
8. Turn the ignition switch OFF.
9. Connect ECM connector C (31P).
10. Turn the ignition switch ON (II).





11. Measure the voltage between ECM connector terminal C15 and body ground.
Is there battery voltage?
YES- Go to step 12.
NO- Replace the ECM.
12. Turn the ignition switch OFF.
13. Disconnect TCM connector B (22P) and ECM connector C (31P).





14. Check for continuity between TCM connector terminal B6 and ECM connector terminal C11.
Is there continuity?
YES- Go to step 15.
NO- Repair open in the wire between TCM connector terminal B6 and ECM connector terminal C11.





15. Check for continuity between TCM connector terminal B6 and body ground, or between ECM connector terminal C11 and body ground.
Is there continuity?
YES- Repair short to ground in the wire between TCM connector terminal B6, ECM connector terminal C11, and ground.
NO- Go to step 16.
16. Connect ECM connector C (31P).
17. Turn the ignition switch ON (II).





18. Measure the voltage between TCM connector terminal B6 and body ground.
Is there about 10 V?
YES- Go to step 19.
NO- Check for loose terminal fit in the ECM connectors. If necessary, substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM.
19. Turn the ignition switch OFF.
20. Connect TCM connector B (22P).
21. Turn the ignition switch ON (II).





22. Measure the voltage between TCM connector terminal B6 and body ground.
Is there battery voltage?
YES- Substitute a known-good TCM and recheck. If the check results are same, replace the ECM.
NO- Replace the TCM.