DTC: U0401-68

DTC U0401-68  : ECM Failure

NOTE: 

• Before You Troubleshoot, Review The General Troubleshooting Information .
• VSA will set this DTC if any PGM-FI DTC's exist.

DTCs (VSA)

1. Problem verification

   -1. Turn the vehicle to the ON mode.

   - 2. Clear the DTC with the HDS.

   - 3. Turn the vehicle to the OFF (LOCK) mode, then start the engine.

   - 4. Check for DTCs with the HDS.

   DTC Description	DTC	Freeze Frame
   U0401-68 ECM Failure

   Is DTC U0401-68 indicated?

   YES 

   The failure is duplicated. Go to step 2.

   NO 

   Intermittent failure, the system is OK at this time. Refer To Intermittent Failures Troubleshooting . If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the Freeze data/on-board snapshot.

2. PGM-FI DTCs check

   -1. Check for PGM-FI DTCs with the HDS.

   DTC Description	Confirmed DTC	Pending DTC	Freeze Frame

   Are any DTCs indicated?

   YES 

   Go to indicated DTCs troubleshooting. After all PGM-FI DTC's have been repaired, return to VSA and clear this code.

   NO 

   Go to step 3.

3. PCM check (substitution)

   -1. Substitute a known-good PCM.

   - 2. Clear the DTC with the HDS.

   - 3. Turn the vehicle to the OFF (LOCK) mode, then start the engine.

   - 4. Check for DTCs with the HDS.

   DTC Description	DTC	Freeze Frame
   U0401-68 ECM Failure

   Is DTC U0401-68 indicated?

   YES 

   Check for loose terminals and poor connections in the VSA modulator-control unit 38P connector. If they are OK, replace the VSA Modulator-Control Unit. Refer to:

   Replace The VSA Modulator-Control Unit

   NO 

   If the PCM was substituted, replace the original PCM - Refer to:

   PCM Removal and Installation (9-Speed A/T) (2019 2020 2021) or

   PCM Removal and Installation .