OBD-II code · Powertrain (generic, extended)
P2A02 O2 Sensor Circuit Range/Performance Bank 1 Sensor 3
The optional third oxygen sensor on bank 1 (typically downstream of a second catalyst) returns implausible values during long-term monitoring.
Is it safe to drive with P2A02?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelySensor aging
- Less likelySensor element aged beyond calibration window
- Less likelySensor mounting loose - signal damping
Symptoms
- Check engine light on
- Increased fuel consumption
- Possible rough idle or hesitation
- Failed emissions test
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.5–1.5 h
- Emissions test
- Likely to fail
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Oxygen Sensor, Catalytic Converter
Related codes
- P2A00O2 Sensor Circuit Range/Performance Bank 1 Sensor 1
- P2A01O2 Sensor Circuit Range/Performance Bank 1 Sensor 2
- P2A03O2 Sensor Circuit Range/Performance Bank 2 Sensor 1
- P2A04O2 Sensor Circuit Range/Performance Bank 2 Sensor 2
- P2A05O2 Sensor Circuit Range/Performance Bank 2 Sensor 3
- P2A06O2 Sensor Circuit Range/Performance Bank 1 Sensor 4
- P2A07O2 Sensor Circuit Range/Performance Bank 2 Sensor 4
- P28FAExhaust Pressure Too Low Bank 2
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.