C0400
Traction Control Solenoid Valve Circuit
The dedicated traction control isolation valve in the hydraulic block reports an electrical fault.
The dedicated traction control isolation valve in the hydraulic block reports an electrical fault.
Common causes
- high
Solenoid coil open
One of the most commonly reported causes for this code — check this first.
Typical part cost: $440-1760
- medium
Short to ground
A plausible cause — test and verify before replacing parts.
Typical part cost: $440-1760
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does C0400 mean?
C0400 means "Traction Control Solenoid Valve Circuit". It is a generic OBD-II code that points to a fault in the chassis.
What are the most common causes of C0400?
solenoid coil open; short to ground — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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