P2E91
Battery Charger B Internal Power Supply Performance
The internal low-voltage power supply of battery charger B does not maintain the expected output. Internal regulator drift or overload.
The internal low-voltage power supply of battery charger B does not maintain the expected output. Internal regulator drift or overload.
Common causes
- high
Internal regulator drifted
One of the most commonly reported causes for this code — check this first.
Typical part cost: $440-2750
- medium
Internal load increased
A plausible cause — test and verify before replacing parts.
Typical part cost: $440-2750
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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 P2E91 mean?
P2E91 means "Battery Charger B Internal Power Supply Performance". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P2E91?
internal regulator drifted; internal load increased — 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?
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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