OBD-II Code · Chassis
C0121
Valve Relay Circuit Malfunction
medium severitySafe to drive$100-$500
ABS valve relay fault.
Common symptoms
- ABS inoperative
- ABS light
Likely causes
- Failed relay
- Wiring
Where to start
- Try the cheapest cause first. Start by checking: failed relay.
- Cost & scope. $100-$500
- If the code returns after the fix: escalate to a shop or scanner with live-data and freeze-frame. A code that re-sets means the underlying fault is still there.
Related codes
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