P063A

Generator Voltage Sense Circuit A

Moderate severity

A general circuit fault is detected on the alternator voltage sense line A - the line over which the regulator measures battery-side voltage to set charging output.

Common causes

Open in sense line
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $90-390
Pack cell imbalance approaching service threshold
Less common, but worth ruling out after the more likely causes.
low
Typical part cost: $90-390
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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 P063A mean?

P063A means "Generator Voltage Sense Circuit A". 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 P063A?

open in sense line; pack cell imbalance approaching service threshold; ground point with elevated resistance — 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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