Code result
C0078
Tire Diameter
Moderate severity
What it means
Detected wheel speed implies tire diameter outside expected range — typically wrong tire size or mismatched tires.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Wrong tire size or mismatch
highOne of the most commonly reported causes for this code — check this first.
Related help
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