U0100
DTC U0100 (55): Motor Control Module (MCM) Lost Communication with PCM1. Connect the HDS.
2. Turn the ignition switch ON (II), and read the HDS.
Does the HDS communicate with the PCM?
YES - Go to step 3.
NO - Go to "DLC Circuit Troubleshooting". If no problem is found in the DLC troubleshooting.
3. Check for Temporary DTCs or DTCs of the PGM-FI system with the HDS.
Is DTC U0037 indicated?
YES - Do the troubleshooting for DTC U0037.
NO - Go to step 4.
4. Reset the MCM.
5. Check for Temporary DTCs or DTCs with the HDS.
Is DTC U0100 indicated?
YES - Go to step 6.
NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the PCM and the MCM.
6. Check for Temporary DTCs or DTCs of the PGM-FI system with the HDS.
Are DTC U1201, U0110, and U0164 indicated at same time?
YES - Go to step 7.
NO - Go to step 15.
7. Turn the ignition switch OFF.
8. Turn the battery module switch OFF.
9. Remove the IPU lid.
10. Disconnect MCM connector A (31P).
11. Jump the SCS line with the HDS.
12. Disconnect PCM connector D (17P).
13. Disconnect the A/C compressor driver 4P connector.
14. Connect PCM connector terminals D13 and D1 to body ground with a jumper wire individually.
15. Check for continuity between MCM connector terminals AT A6 and body ground, and between A/C compressor driver 4P connector terminals No. 2, No. 3 and body ground individually.
Is there continuity?
YES - Go to step 16.
NO - Repair open in the wire between the A/C compressor driver, the MCM (A7, A6), and the PCM (D13, D1)
16. Check for Temporary DTCs or DTCs with the HDS.
Is DTC U0164 indicated?
YES - Go to step 17.
NO - Go to step 20.
17. Reinstall the IPU lid, then turn the battery module switch ON.
18. Update the MCM if it does not have the latest software, or substitute a known-good MCM.
19. Check for Temporary DTCs or DTCs with the HDS.
Are any Temporary DTCs or DTCs indicated?
YES - If DTC U0100 is indicated, check for poor connections or loose terminals at the PCM and the MCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.
NO - If the MCM was updated, troubleshooting is complete. If the MCM was substituted, replace the original MCM.
20. Reinstall the IPU lid, then turn the battery module switch ON.
21. Update the PCM if it does not have the latest software, or substitute a known-good PCM.
22. Check for Temporary DTCs or DTCs with the HDS.
Are any Temporary DTCs or DTCs indicated?
YES - If DTC U0100 is indicated, check for poor connections or loose terminals at the PCM and the MCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.
NO - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM.