C0727

Trailer Connector Circuit Malfunction

Moderate severity

The chassis or trailer brake module has detected a fault in the trailer wiring connector — for example open lighting circuit or short to ground. Trailer brake and lighting functions may be unavailable.

Common causes

Connector pins corroded or bent
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $40-330
Short or open in trailer wiring
A plausible cause — test and verify before replacing parts.
medium
Typical part cost: $40-330
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First things to check

1Confirm the code with a scan tool and check for additional related codes.
2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.

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Related codes

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Frequently asked questions

What does C0727 mean?

C0727 means "Trailer Connector Circuit Malfunction". It is a generic OBD-II code that points to a fault in the chassis.

What are the most common causes of C0727?

connector pins corroded or bent; short or open in trailer wiring — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.

Can I keep driving with this code?

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.

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