Right front wheel speed sensor B internal failure, shorting the signal line to voltage; Damaged or chafed sensor wiring harness shorted to a power source; Corroded or loose electrical connector at the sensor or ABS module; Metal debris or a damaged tone ring interfering with the sensor signal; Faulty ABS control module interpreting the signal incorrectly; Aftermarket or incorrect sensor installed that does not match the vehicle's specification

DTC codes / C06xx · Brakes, steering and suspension / C065B

C065BRight Front Wheel Speed Sensor B Circuit High

Q: What does code C065B mean?

Right Front Wheel Speed Sensor B Circuit High. The anti-lock braking system (ABS) module has detected an abnormally high voltage on the signal circuit for the right front wheel speed sensor B, which is the sensor's second signal line used for redundancy or direction detection. This means the circuit is seeing voltage above the expected range, often because the signal wire is shorted to power or the sensor's internal electronics have failed.

The anti-lock braking system (ABS) module has detected an abnormally high voltage on the signal circuit for the right front wheel speed sensor B, which is the sensor's second signal line used for redundancy or direction detection. This means the circuit is seeing voltage above the expected range, often because the signal wire is shorted to power or the sensor's internal electronics have failed.

SystemChassis

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaBrakes, steering and suspension

Symptoms you may notice

ABS warning light illuminated on the dashboard
Traction control or stability control warning light also on
Often no symptoms besides the warning light, with normal brake pedal feel
ABS may deactivate, allowing wheel lockup during hard braking
Traction control may stop intervening, causing wheel spin on slippery surfaces
In some vehicles, a chime or message about a brake system fault

Common causes, most likely first

Right front wheel speed sensor B internal failure, shorting the signal line to voltage
Damaged or chafed sensor wiring harness shorted to a power source
Corroded or loose electrical connector at the sensor or ABS module
Metal debris or a damaged tone ring interfering with the sensor signal
Faulty ABS control module interpreting the signal incorrectly
Aftermarket or incorrect sensor installed that does not match the vehicle's specification

How to diagnose and fix it

Scan all modules and record freeze-frame data to confirm C065B is current and not historical
Visually inspect the right front sensor wiring and connector for chafing, corrosion, or loose pins
Measure voltage on the sensor B signal circuit with a digital multimeter and compare to specification
Check the sensor's resistance and output with a scope or multimeter while spinning the wheel
Inspect the tone ring for cracks, missing teeth, or metal debris and clean or replace as needed
Substitute a known-good sensor or perform a wiggle test on the harness to isolate an intermittent short
If the circuit and sensor test good, diagnose the ABS module and its power/ground circuits

Why a high signal does not always mean a bad sensor

A short to voltage on the signal wire often comes from a harness rubbed through near the strut tower or inner fender, not from the sensor itself.
Some vehicles use the B circuit for direction detection, so a failure can set the code without any traditional ABS symptom.
Aftermarket sensors with incorrect internal resistance are a common cause of repeated high-voltage codes after a recent brake or suspension repair.
A weak or failing ABS module ground can cause the module to misread sensor voltage as high, leading to unnecessary sensor replacement.
Metal debris stuck to the tone ring can generate a voltage spike that the module interprets as a high signal, so always clean the ring before condemning parts.

Can I keep driving with C065B?

You can usually drive the vehicle, but the ABS and traction control systems may be disabled, so allow extra braking distance and avoid slippery or loose surfaces. Have the fault diagnosed soon, especially if the brake warning light is also on.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.