P1031
Air Fuel Ratio Sensor 1 Heater Control Circuit Low Bank 1
Severity
⚠️ MediumCan you drive?
Yes, but get it checked soon
Approx. repair cost
$33–89 (est.)
Symptoms
- Check Engine light comes on
- Deteriorating fuel economy
- Unstable engine operation at idle
- Increased emissions
- Reduced engine power
Causes
- Open or short circuit in the AFR sensor heater circuit
- Air-fuel ratio sensor malfunction
- Problems with the wiring harness or connectors
- Engine control module (ECU) malfunction
- Corrosion or poor contact in electrical connections
How to Fix
- Check the continuity of the AFR sensor heater circuit
- Inspect connectors and wiring harness for damage
- Check sensor heater resistance
- Replace the air-fuel ratio sensor if necessary
- Check and, if necessary, replace the engine control module