Code result
C0400
Traction Control Solenoid Valve Circuit
Moderate severity
What it means
The dedicated traction control isolation valve in the hydraulic block reports an electrical fault.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Solenoid coil open
highOne of the most commonly reported causes for this code — check this first.
Short to ground
mediumA plausible cause — test and verify before replacing parts.
Related help
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