Powertrain
Definition only
Lights the check engine lamp
P2A3B: O2 Sensor Negative Current Control Circuit/Open Bank 1 Sensor 3
Standardized SAE J2012 code · P2Axx codes
What does P2A3B mean?
The control circuit for the wide-band oxygen sensor negative current pump on bank 1 sensor 3 is open. Pumping current cannot be applied for lambda regulation.
The code tells you which monitor failed, not which part is broken. Test before replacing parts.
Symptoms
- Check engine light on
- Increased fuel consumption
- Possible rough idle or hesitation
- Failed emissions test
Common causes
- High Open in pump current wire
- Medium Internal open in pump cell
- Low Pin pushed back out of connector body
Likelihood is a general estimate across vehicles; your make and model may differ.
Add your car to see reports of P2A3B on the same make and model first.
P2A3B in the community
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