P0031 BMW Possible Causes
- Faulty Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1
- Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1 harness is open shorted to ground
- Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1 circuit poor electrical connection
- Heated Oxygen Sensor (H2OS) Bank 1 Sensor 1 circuit fuse
- Faulty Engine Control Module (ECM)
How do I fix code P0031 BMW
Check the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.
P0031 BMW Tech NotesThe code means that there is a problem with the heater element circuit of the heated oxygen sensor. Water getting inside the heated oxygen sensor connector can caused the heated oxygen sensor fuse to blow, which is a very common problem for this type codes. Before replacing the sensor, check for the condition of the heated oxygen sensor fuse and connectors.
Cost of diagnosing the P0031 BMW code
Labor: 1.0The cost of diagnosing the P0031 BMW code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.
When is the P0031 BMW code detected?The P0031 is set when the ECM detects an excessively low voltage through the heated oxygen sensor heater circuit
P0031 BMW Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
P0031 BMW MeaningOxygen Sensors (O2S) or Heated Oxygen Sensors (HO2S) need to reach a minimum operating temperature of 750 degrees F to produce an accurate voltage signal. The faster the heated oxygen sensor reaches that temperature the faster the sensor will start sending an accurate signal to the Engine Control Module (ECM).
In order to achieve the require temperature, a heater element is included inside the heated oxygen sensor. The ECM controls the heated oxygen sensor heater element based on signals from the engine coolant temperature and engine load. The ECM controls the heater element circuit by allowing current flow to ground.
The ECM monitors the voltage signal received through the heater element circuit and determines the state of the circuit by comparing the voltage detected with the factory specifications.
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