OBD-II code · Powertrain (generic)
P0147 O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 3)
The ECU detects an electrical fault in the heater circuit of the third O2 sensor on bank 1. Heater current out of range, indicating open/shorted heater element, blown fuse or wiring fault.
Is it safe to drive with P0147?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyHeater element open
- PossibleHeater fuse blown
Symptoms
- Check engine light on after several drive cycles
- Slightly increased fuel consumption during cold start
- Delayed entry into closed-loop fuel control
- Failed emissions inspection (lambda readiness)
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 B1s3, Oxygen Sensor Heater Fuse, Oxygen Sensor Heater Wiring
Related codes
- P0142O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)
- P0162O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 2)
- P0167O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 3)
- P0144O2 Sensor Circuit Low Voltage (Bank 1 Sensor 3)
- P0145O2 Sensor Circuit High Voltage (Bank 1 Sensor 3)
- P0146O2 Sensor Circuit No Activity / Slow Response (Bank 1 Sensor 3)
- P0148Fuel Delivery Error
- P0149Fuel Timing Error
- P014AO2 Sensor Delayed Response - Rich to Lean Bank 2 Sensor 2
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.