C0171 critical

Electronic Brake Control Module Relay Circuit Open

The C0171 code means the vehicle's onboard diagnostic system has detected: Electronic Brake Control Module Relay Circuit Open. This is a critical severity code.

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Keep driving?: No -- stop driving
DIY difficulty: hard
Estimated cost: $50 - $800 (parts and labor)

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Common Symptoms

ABS completely inoperative
Traction control disabled
Brake warning light on
Electronic stability control fault

Probable Causes (Ranked by Likelihood)

Failed ABS relay or relay coil Very High
Open or shorted circuit in relay wiring High
Corroded relay socket terminals Moderate
EBCM internal relay driver failure Low

Step-by-Step Diagnostic Procedure

Check ABS fuse and relay in underhood fuse box
Test relay by swapping with known good relay
Measure voltage at relay coil and contact terminals
Check EBCM relay driver circuit

Frequently Asked Questions

What does code C0171 mean?

Code C0171 indicates electronic brake control module relay circuit open. This is a chassis-related diagnostic trouble code stored in your vehicle's on-board computer.

Can I drive with code C0171?

You should not drive with this code active as it affects critical safety systems.

How much does it cost to fix C0171?

Typical repair costs range from $50 - $800 (parts and labor). The actual cost depends on the root cause, vehicle make and model, and local labor rates. Get a proper diagnosis before replacing parts.