What P0031 means
Circuito de control del sensor de oxígeno bajo (Banco 1 Sensor 1)
Common causes (general)
Before spending money on parts, verify the code with a scan tool and read freeze frame data. Freeze frame captures every sensor value at the moment the code set — this is often enough to figure out the root cause without further testing.
Manufacturer-specific descriptions
Different manufacturers use this code for slightly different failure modes. Here's what your specific make means by P0031:
| BMW | HO2S Heater Control Circuit Low |
| MITSUBISHI | HO2S Heater Control Circuit Low (Bank 1 Sensor 1); Oxygen sensor heater(front) low |
| NISSAN | HO2S Heater Control Circuit Low (Bank 1 Sensor 1) |
| VOLKSWAGEN | HO2S Heater Circuit Low Voltage Bank 1 Sensor 1 |
Read this code on your own car
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