Connect scantool to Data Link Connector(DLC).

Self-diagnose 4WD ECM with scantool.

Check the change of each wheel speed sensor's value according to the change of vehicle speed.(Refer to Fig.1)

If the sensor's value is stuck, self-diagnose VDC ECM with scantool. So if there are any DTCs related to the sensor, inspect it at first and check if the DTCs have been erased.

In a case that there is no DTC, select "RPM" item among the service data.(Refer to Fig.2)

Check the change of the sensor's value according to a vehicle's speed.

Fig 1) Wheel Speed Velocity(4WD)

Fig 2) Wheel Speed Sensor(VDC)

Is parameter displayed within specifications?

	▶ Fault is intermittent caused by poor contact in the sensor’s and/or ECM’s connector or was repaired and ECM memory was not cleared. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of vehicle Repair" procedure.
	▶ Go to "Inspection/Repair" procedure.