P2AB2
Catalyst Heater Control Module Supply Voltage
The catalyst heater control module reports supply voltage outside the expected window. Heating output cannot be regulated as expected.
The catalyst heater control module reports supply voltage outside the expected window. Heating output cannot be regulated as expected.
Common causes
- high
Module supply fuse blown
One of the most commonly reported causes for this code — check this first.
Typical part cost: $110-550
- medium
Alternator regulator drift
A plausible cause — test and verify before replacing parts.
Typical part cost: $110-550
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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 P2AB2 mean?
P2AB2 means "Catalyst Heater Control Module Supply Voltage". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P2AB2?
module supply fuse blown; alternator regulator drift — 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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