Powertrain
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Lights the check engine lamp
P2A01: O2 Sensor Circuit Range/Performance Bank 1 Sensor 2
Standardized SAE J2012 code · P2Axx codes
What does P2A01 mean?
The rear oxygen sensor on bank 1 does not show the expected slow steady-state behaviour after the catalyst. Either the sensor is degraded or the catalyst itself behaves abnormally.
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 Sensor aging
- Medium Catalyst aging
- Low Sensor element aged beyond calibration window
Likelihood is a general estimate across vehicles; your make and model may differ.
Add your car to see reports of P2A01 on the same make and model first.
P2A01 in the community
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Describe your P2A01 problemRelated codes
- P2A00 O2 Sensor Circuit Range/Performance Bank 1 Sensor 1
- P2A02 O2 Sensor Circuit Range/Performance Bank 1 Sensor 3
- P2A03 O2 Sensor Circuit Range/Performance Bank 2 Sensor 1
- P2A04 O2 Sensor Circuit Range/Performance Bank 2 Sensor 2
- P2A05 O2 Sensor Circuit Range/Performance Bank 2 Sensor 3
- P2A06 O2 Sensor Circuit Range/Performance Bank 1 Sensor 4
- P2A07 O2 Sensor Circuit Range/Performance Bank 2 Sensor 4