P2A39
O2 Sensor Positive Current Control Circuit Low Bank 1 Sensor 3
Voltage on the wide-band oxygen sensor positive pump current line of bank 1 sensor 3 is below the expected window. Wire shorted to ground or pump cell short.
Voltage on the wide-band oxygen sensor positive pump current line of bank 1 sensor 3 is below the expected window. Wire shorted to ground or pump cell short.
Common causes
- high
Pump current wire shorted to ground
One of the most commonly reported causes for this code — check this first.
Typical part cost: $170-770
- medium
Internal short in pump cell
A plausible cause — test and verify before replacing parts.
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 P2A39 mean?
P2A39 means "O2 Sensor Positive Current Control Circuit Low Bank 1 Sensor 3". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P2A39?
pump current wire shorted to ground; internal short in pump cell; connector pins corroded - high contact 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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