Code result
P063B
Generator Voltage Sense Circuit A Range or Performance
Moderate severity
What it means
Same as P063A with the sense voltage in plausible range yet not matching the alternator output - high contact resistance or wrong calibration.
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
Contact resistance high
highOne of the most commonly reported causes for this code — check this first.
Pack cell imbalance approaching service threshold
lowLess common, but worth ruling out after the more likely causes.
Ground point with elevated resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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