Code result
C0121
Valve Relay Circuit Malfunction
Moderate severity
What it means
The ABS control module has detected a fault in the valve relay circuit, which supplies power to the ABS solenoid valves. With this fault, the module cannot energize the valves and ABS is disabled.
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
Valve relay failed
highOne of the most commonly reported causes for this code — check this first.
Internal ABS module fault (relay integrated)
mediumA plausible cause — test and verify before replacing parts.
Power supply wiring or fuse fault
lowLess common, but worth ruling out after the more likely causes.
Related help
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