P0031

Symptoms

• Increased fuel consumption
• Rough engine idle
• Loss of engine power
• Increased exhaust toxicity
• Check Engine Light Illuminates
• Difficulty starting a cold engine

Causes

• Open or short circuit in the heating circuit wiring
• Oxygen sensor malfunction
• Oxidation or corrosion of connectors
• Malfunction of the oxygen sensor heating relay
• Damage to the heating circuit fuse
• Engine control unit (ECU) malfunction

How to Fix

1. Read error codes and analyze data from the diagnostic scanner
2. Check the fuses and relays of the oxygen sensor heating circuit.
3. Inspect the wiring for damage, breaks and corrosion
4. Measure the resistance of the sensor heating element (should be 2-14 Ohms)
5. Check the supply voltage at the sensor connector with the engine running
6. If necessary, replace the oxygen sensor
7. Clean connectors and repair damaged wiring
8. Clear error codes and take a test drive

Related codes

Error P0031 by Vehicle Brand