DTC Advanced Diagnostics: C0031-3A

DTC C0031-3A: Wheel Speed Sensor (Left Front) Signal Failure (Signal Frequency is Too High)

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 9.6 - 16.5 V

With the Driving Pattern:

1.	Start the engine.
2.	Test-drive the vehicle for 80 seconds or more. (Be careful of the surrounding traffic conditions.)

Execution

Regular Diagnosis

Duration

About 80 seconds

DTC Type

	1 drive cycle
	Brake system indicator (red) on (If multiple wheel failures are detected)
	Brake system indicator (amber) on
	ABS indicator on
	VSA indicator on

Fail Safe Action

	Stop EBD function (If multiple wheel failures are detected)
	Stop ABS function
	Stop engine drag torque control function
	Stop TCS function
	Stop VSA function
	Stop agile handling assist function
	Stop brake assist function
	Stop hydraulic boost failure compensation function
	Stop hill start assist function
	Stop automatic brake hold function
	Stop automatic operating function (Drive away assist)
	Stop automatic operating function (Request from other system) (Dependant upon the conditions)
	Stop ignition OFF apply function
	Stop ACC function*
	Stop CMBS function*

Possible Cause

	Electrical noise in the left-front wheel speed sensor signal
	Left-front wheel speed sensor incorrect installation
	Debris on the left-front encoder surface
	Left-front wheel speed sensor failure
	VSA modulator-control unit internal failure

*: With ACC