C0631

Symptoms

• All-wheel drive does not engage when selecting 4WD mode
• The 4WD indicator on the dashboard is flashing
• Extraneous noises (grinding, clicking) from the front axle area
• Vibration when driving in 4WD mode
• Service 4WD message on display

Causes

• Front axle actuator motor malfunction
• Worn shift fork in the actuator
• Broken or damaged wiring to the actuator
• Vacuum leak (for vacuum connection systems)
• Mechanical jamming of the front axle clutch
• Corrosion of the mechanism due to water ingress

How to Fix

1. Read error codes with an all-wheel drive scanner
2. Check the operation of the actuator - apply power directly and make sure it moves
3. Inspect the wiring and connector of the front axle actuator
4. For vacuum systems - check the integrity of the vacuum hoses and the operation of the vacuum pump
5. Check the mechanical condition of the shift fork and clutch
6. Replace the actuator if the electric motor or mechanical part is faulty

Related codes

Error C0631 by Vehicle Brand