C0784

Trailer Brake Force Sensor Circuit Malfunction

Moderate severity

The integrated trailer brake controller has detected an electrical fault in the brake force sensor circuit. Proportional trailer brake control is disabled — the controller defaults to a manual or fixed-gain mode.

Common causes

Trailer brake force sensor failed
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $170-770
Wiring or connector fault
A plausible cause — test and verify before replacing parts.
medium
Typical part cost: $170-770
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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 C0784 mean?

C0784 means "Trailer Brake Force Sensor Circuit Malfunction". It is a generic OBD-II code that points to a fault in the chassis.

What are the most common causes of C0784?

trailer brake force sensor failed; wiring or connector fault — 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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