P0031 2003 TOYOTA HIGHLANDER - Oxygen Sensor Heater Control Circuit Low Bank 1 Sensor 1
P0031 2003 TOYOTA HIGHLANDER Possible Causes
- Faulty Air-Fuel Ratio (A/F) Sensor Bank 1 Sensor 1
- Air-Fuel Ratio (A/F) Sensor Bank 1 Sensor 1 harness is open shorted to ground
- Air-Fuel Ratio (A/F) Sensor Bank 1 Sensor 1 circuit poor electrical connection
- Air-Fuel Ratio (A/F) Sensor Bank 1 Sensor 1 circuit (EFI relay)
- Faulty Engine Control Module (ECM)
How do I fix code P0031 2003 TOYOTA HIGHLANDER?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.
Cost of diagnosing the P0031 2003 TOYOTA HIGHLANDER code
Labor: 1.0The cost of diagnosing the P0031 2003 TOYOTA HIGHLANDER 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 code detected?The P0031 is set when the ECM detects an excessively low voltage through the heated oxygen sensor heater circuit
- Engine Light ON (or Service Engine Soon Warning Light)
P0031 2003 TOYOTA HIGHLANDER MeaningAir-Fuel Ratio (A/F)sensor need to reach a minimum operating temperature of 1200 degrees F to produce an accurate voltage signal. The faster the air-fuel ratio 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 air-fuel ratio sensor. The ECM controls the air-fuel ratio 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.
P0031 2003 TOYOTA HIGHLANDER More InformationNeed more information on how to fix the P0031 2003 TOYOTA HIGHLANDER code?
Get Access to Factory Service Manuals