Trouble codes › P0037
P0037 HO2S Heater Control Circuit Low (Bank 1 Sensor 2)
Oxygen sensors
P0037 means the heater circuit of bank 1's rear oxygen sensor reads low, usually because the sensor's heater has burned out.
The heater circuit for the rear oxygen sensor on bank 1 (after the catalytic converter) is reading low, usually because the heater is open or has lost power.
Safe to drive. It mainly affects the catalytic converter monitor and emissions readiness.
Common causes
- A burned-out heater in the rear oxygen sensor
- A blown fuse
- An open wire or corroded connector (rear sensors get road splash)
Symptoms
- Check-engine light
- Emissions monitors may not be ready for an inspection
What to check first
- Check the heater fuse.
- Measure the heater resistance at the rear sensor.
- Inspect wiring under the car for damage.
- Replace the sensor if the heater is open.
What does P0037 mean on your vehicle?
The likely cause depends on your engine. iRepair researches your exact year, make, model and engine (service bulletins, recalls and owner reports) and tells you what to check first. Your first 3 questions are free.
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Related codes
General guidance for P0037 on most vehicles. Some makers use the same code a little differently; confirm in the service information for your vehicle, put safety first, and see a professional when in doubt.