Question 1

What does P0031 mean?

Accepted Answer

P0031 - O2 Sensor Heater Circuit Low (Bank 1 Sensor 1). Low voltage in upstream O2 sensor heater circuit — heater has likely burned out.

Question 2

What are the symptoms of P0031?

Accepted Answer

Check engine light, Poor cold-start performance

Question 3

What causes P0031?

Accepted Answer

Burned-out heater, Broken wire, Loose connector, Blown fuse

Question 4

How much does it cost to fix P0031?

Accepted Answer

Typical repair cost: $100-$300. Low circuit code almost always means the heater inside the O2 sensor has failed. Replace sensor.

P0031 — O2 Sensor Heater Circuit Low (Bank 1 Sensor 1)

Don't guess — diagnose P0031 the right way