C05A8
ABS Pump Motor Supply Voltage B Circuit Range/Performance
ABS pump motor supply B drifts or fluctuates. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
ABS pump motor supply B drifts or fluctuates. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
Common causes
- high
Connector with high resistance
One of the most commonly reported causes for this code — check this first.
Typical part cost: $30-440
- low
Sensor element aged beyond calibration window
Less common, but worth ruling out after the more likely causes.
Typical part cost: $30-440
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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
See related trouble codes
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Frequently asked questions
What does C05A8 mean?
C05A8 means "ABS Pump Motor Supply Voltage B Circuit Range/Performance". It is a generic OBD-II code that points to a fault in the chassis.
What are the most common causes of C05A8?
connector with high resistance; sensor element aged beyond calibration window; sensor mounting loose - signal damping — 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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