W/Harness Inspection

P0031 HO2S Heater Control Circuit Low (Bank 1 / Sensor 1)

Inspection/Repair - W/Harness Inspection

Power Circuit Inspection

1. Ignition "OFF"
2. Disconnect HO2S sensor connector.
3. Ignition "ON" & Engine "OFF"
4. Measure voltage between power terminal of the HO2S heater harness connector and chassis ground.

Specification :B+




5. Is voltage display near the specified value?






Control Circuit Inspection

1. Measure voltage between control terminal of the HO2S heater harness connector and chassis ground.

Specification :Approx. 4 - 5 V




2. Is voltage display near the specified value?






Terminal and Connector Inspection

1. Many malfunctions in the electrical system are caused by poor harness(es) and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Has a problem been found?