OBD-II code · Powertrain (generic)
P0165 O2 Sensor Circuit High Voltage (Bank 2 Sensor 3)
The ECU detects abnormally high voltage from the third O2 sensor on bank 2. Indicates rich exhaust or wiring shorted to voltage.
Is it safe to drive with P0165?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyRich exhaust condition
- PossibleSignal wire shorted to voltage
- Less likelyConnector pins corroded - high contact resistance
Symptoms
- Check engine light on
- Increased fuel consumption
- Possible rough idle or hesitation
- Failed emissions test
Repair at a glance
- Difficulty
- Easy
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.3–1.5 h
- Emissions test
- Likely to fail
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Oxygen Sensor B2s3, Oxygen Sensor Wiring
Related codes
- P0139O2 Sensor Circuit High Voltage (Bank 1 Sensor 2)
- P0145O2 Sensor Circuit High Voltage (Bank 1 Sensor 3)
- P0153O2 Sensor Circuit High Voltage (Bank 2 Sensor 1)
- P0159O2 Sensor Circuit High Voltage (Bank 2 Sensor 2)
- P0162O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 2)
- P0163O2 Sensor Circuit Malfunction (Bank 2 Sensor 3)
- P0164O2 Sensor Circuit Low Voltage (Bank 2 Sensor 3)
- P0166O2 Sensor Circuit No Activity / Slow Response (Bank 2 Sensor 3)
- P0167O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 3)
- P0168Fuel Temperature Too High
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.