AT-PZEV Models
DTC P1655: Problem in TCM-to-ECM Communication Lines2003 AT-PZEV (SULEV) and 2004-2005 AT-PZEV Models
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. Wait for 1 minute. If the radiator fan is running, wait for 1 minute after the radiator fan stops.
3. Disconnect TCM connector C (17P) and ECM connector B (24P).
4. Check for continuity between TCM connector terminal C17 and ECM connector terminal B24.
Is there continuity?
YES- Go to step 5.
NO- Repair open in the wire between TCM connector terminal C17 and ECM connector terminal B24.
5. Check for continuity between TCM connector terminal C17 and body ground, or between ECM connector terminal B24 and body ground.
Is there continuity?
YES- Repair short to ground in the wire between TCM connector terminal C17 and ECM connector terminal B24.
NO- Go to step 6.
6. Connect TCM connector C (17P).
7. Turn the ignition switch ON (II).
8. Measure the voltage between ECM connector terminal B24 and body ground.
Is there about 10 V?
YES- Go to step 9.
NO- Check for loose or poor connections at TCM connector terminals. If the connections are OK, update the TCM if it does not have the latest software, or substitute a known-good TCM, then recheck. If the symptom/indication goes away with a known-good TCM, replace the original TCM..
9. Turn the ignition switch OFF.
10. Connect ECM connector B (24P).
11. Turn the ignition switch ON (II).
12. Measure the voltage between ECM connector terminal B24 and body ground.
Is there about 10 V?
YES- Go to step 13.
NO- Update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM.
13. Turn the ignition switch OFF.
14. Wait for 1 minute. If the radiator fan is running, wait for 1 minute after the radiator fan stops.
15. Disconnect TCM connector C (17P) and ECM connector B (24P).
16. Check for continuity between TCM connector terminal C16 and ECM connector terminal B22.
Is there continuity?
YES- Go to step 17.
NO- Repair open in the wire between TCM connector terminal C16 and ECM connector terminal B22.
17. Check for continuity between TCM connector terminal C16 and body ground, or between ECM connector terminal B22 and body ground.
Is there continuity?
YES- Repair short to ground in the wire between TCM connector terminal C16 and ECM connector terminal B22.
NO- Go to step 18.
18. Connect ECM connector B (24P).
19. Turn the ignition switch ON (II).
20. Measure the voltage between TCM connector terminal C16 and body ground.
Is there about 10 V?
YES- Update the TCM if it does not have the latest software, or substitute a known-good TCM, then recheck. If the symptom/indication goes away with a known-good TCM, replace the original TCM.
NO- Check for loose or poor connections at ECM connector terminals. If the connections are OK, update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM.