C0504

Q: 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.

Left Front Wheel Speed Sensor A Intermittent/Erratic

High severity

Intermittent or erratic signal from left-front wheel speed sensor A. Wheel-speed signals feed ABS, ESC, traction control, transmission and odometer — a single dropped signal disables all of these safety functions until repaired.

Common causes

Connector loose or chafed wiring
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $40-390
Connector with intermittent contact under vibration
Less common, but worth ruling out after the more likely causes.
low
Typical part cost: $40-390
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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 C0504 mean?

C0504 means "Left Front Wheel Speed Sensor A Intermittent/Erratic". It is a generic OBD-II code that points to a fault in the chassis.

What are the most common causes of C0504?

connector loose or chafed wiring; connector with intermittent contact under vibration; harness routed against vibrating component — 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?

This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.

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