Transmission Control Systems

DTC U0122: Lost Communication with VSA Modulator-Control Unit

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review General Troubleshooting Information.

1. Turn the ignition switch ON (II).
2. Clear the DTC with the HDS.
3. Turn the ignition switch ON (II).
4. Check for Temporary DTCs or DTCs in the PGM-FI SYSTEM with the HDS.
Is DTC U0122 indicated in the PGM-FI SYSTEM?
YES - Go to the DTC U0122 troubleshooting in the PGM-FI system.
NO - Go to step 5.

5. Check for DTCs in the A/T SYSTEM with the HDS.
Is DTC U0122 indicated in the A/T SYSTEM?
YES - Go to step 6.
NO - Intermittent failure, the system is OK at this time.

6. Update the PCM if it does not have the latest software, or substitute a known-good PCM.
7. Turn the ignition switch ON (II).
8. Check for DTCs in the A/T SYSTEM with the HDS.
Is DTC U0122 indicated in the A/T SYSTEM?
YES - Check for poor connections or loose terminals at the PCM. If the PCM was updated, substitute a known-good PCM, then go to step 7. If the PCM was substituted, go to step 1.
NO - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM. If any other DTCs were indicated, go to the indicated DTC's troubleshooting.