ABS Valve Relay Circuit Malfunction
High severity. Avoid long drives and get diagnosed as soon as possible. Flashing check engine light = stop driving if safe.
Quick Answer
C0121 means “ABS Valve Relay Circuit Malfunction.” Severity: High. Estimated repair cost: $50 - $250. Most common sign: ABS warning light.
What Does C0121 Mean?
Common Symptoms
Possible Causes
How to Fix C0121 – Repair Guide
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Budgeting for This Repair?
A typical C0121 repair runs about $50 - $250. If you'd rather spread the cost over time, estimate the payment with our free sister tool: Car Finance Calculator (50-state sales tax, trade-in equity, full amortization).
Recommended OBD2 Scanners & Tools
To read and clear this code yourself, you need a reliable OBD2 scanner. Here are top-rated options:
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Simple plug-and-play sensor that explains codes in plain English via free app. Ideal for first-time users.
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