P065B
Generator A Control Circuit Range or Performance
The PWM control line to the alternator A regulator does not deliver the expected charging response - high contact resistance, regulator drift, or wrong calibration.
The PWM control line to the alternator A regulator does not deliver the expected charging response - high contact resistance, regulator drift, or wrong calibration.
Common causes
- high
Regulator response drifted
One of the most commonly reported causes for this code — check this first.
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
See related trouble codes
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Frequently asked questions
What does P065B mean?
P065B means "Generator A Control Circuit Range or Performance". It is a generic OBD-II code that points to a fault in the computer & auxiliary output controls.
What are the most common causes of P065B?
regulator response drifted — 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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