DTC U0401-68 (VSA Control Unit)

DTC U0401-68 : ECM Failure

NOTE:

Initial Diagnosis:
The initial on-board diagnosis occurs right after the vehicle condition is turned to the ON mode, and the ABS/VSA indicator comes on, and continues until the indicator goes off.
Regular Diagnosis:
The regular on-board diagnosis begins right after the ABS/VSA indicator goes off, and it continues until the vehicle condition is turned to the OFF (LOCK) mode.
Review "How to troubleshoot the VSA system" before doing the DTC troubleshooting procedure.
Test-drive the vehicle according to local traffic conditions and regulations. Do not test-drive on a lift unless specified.
The possible causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.

Confirmation Procedure	Basic Condition: 12 volt battery voltage above 10 V With the Driving Pattern: Start the engine. Test-drive the vehicle at 6 mph (10 km/h) or more for at least 2 seconds. (Be careful of the surrounding traffic conditions.)
Execution	Regular Diagnosis
Duration	About 1 second
DTC Type	1 drive cycle VSA indicator on
Fail Safe Action	Stop VSA function Stop TCS function Stop engine drag torque control function Stop hill start assist function Stop trailer stability assist control function Stop agile handling assist control function
Possible Cause	PCM internal failure (PGM-FI system) VSA modulator-control unit internal failure