P0031 - Oxygen Sensor (A/F) Heater Control Circuit Low (Bank 1 Sensor 1)
Content
DTC P0031 - OBD-II Data Sheet
Common: Oxygen Sensor (A/F) Heater Control Circuit Low (Bank 1 Sensor 1) Nissan Heated Oxygen Sensor (HO2S) 1 Bank 1 - Heater Voltage Low
- P0031 - Oxygen heater sensor (HO2S) heater circuit low voltage bank 1 sensor 1.
What does code P0031 mean?
This Diagnostic Trouble Code (DTC) is a generic transmission code, which means it applies to OBD-II equipped vehicles including but not limited to Toyota, VW, Ford, Dodge, Honda, Chevrolet, Hyundai, Audi, Nissan, etc. E. Specific repair steps may vary depending on the model.
DTC P0031 (Diagnostic Trouble Code) applies to the O2 sensor (oxygen sensor) located on Bank 1 upstream of the catalytic converter. There is also an oxygen sensor behind the transducer, which is sensor # 2.
This # 2 O1 sensor may also be referred to as an air / fuel ratio sensor as it is on some vehicles. It detects the amount of oxygen in the exhaust compared to outside air, and then the car's computer adjusts the air / fuel ratio to the engine. The sensor is less effective at low exhaust temperatures, so it turns on a heater that activates to help get the best reading from the A / F O2 sensor. Basically, this P0031 code means that the resistance of the heater circuit is below normal. In most cases, this resistance level must fall below 0.8 A for the DTC to set.
Please note that this code is very similar in nature to P0032, P0051, and P0052.
Possible symptoms
Most likely you will not notice any symptoms other than the malfunction indicator lamp (check engine lamp) comes on.
- The engine fault light is on.
- This particular fault usually has no more symptoms than the one already mentioned and is very difficult to distinguish from faults in other vehicles.
Causes of the P0031 code
The P0031 DTC can be caused by one or more of the following:
- Short circuit or open circuit in the heater circuit in the sensor
- Defective O2 sensor heater
- Broken / worn wiring / connectors to sensor and / or relay
- Defective PCM / ECM
- Bank 2 HO1S oxygen sensor 1 is completely defective.
- Sensor 1 harness is open or shorted to ground.
- The heated oxygen sensor has faulty fuses.
- The engine control module (ECM) is damaged or defective.
- The wires and connections to the sensor are worn or damaged.
Possible solutions
To fix the P0031 DTC, you need to run proper diagnostics. To do this, you need to inspect the wiring and connectors leading to the sensor. Also, if you have a heater relay and fuse, you will want to test them as well. Use a digital volt-ohmmeter to:
- check for 12 volts on the heater circuit power (hint: disconnect the sensor and check the wiring connector to take this measurement)
- check the ground circuit for continuity
- measure the resistance of the heater circuit (done on the sensor itself)
- measure the resistance and voltage of the wiring
Refer to your service manual for the correct specifications (volts, ohms) for your vehicle. On some Toyota vehicles, this code is triggered when the resistance of the heater circuit is below 0.8 A.
With that said, the usual solution for this DTC is to replace the # 2 Air / Fuel (O1, Oxygen) sensor on Bank 1.
Note that replacement of OEM sensors (original equipment) is recommended (by dealer). Aftermarket sensors may be less reliable and of lower quality (not always, but more often). There is also the possibility that parts code P0031 may also be eligible for a federal emissions guarantee (check with your dealer if this applies).
Repair Tips
After the vehicle is taken to the workshop, the mechanic will usually perform the following steps to properly diagnose the problem:
- Scan for error codes with an appropriate OBC-II scanner. Once this is done and after the codes have been reset, we will continue to test drive on the road to see if the codes reappear.
- Visual inspection of wiring for bare wires or short circuits.
- With the key inserted and the engine off, use a voltmeter to check the power to the battery.
- Check for oxygen sensors that may be faulty.
Although the cause of this DTC is most often a defective heated oxygen sensor (HO2S), it is not recommended to rush to replace this component without a thorough check first. Before you decide on this solution, you will actually need to carefully check all the cables connected to this device and the connector itself. After all, the problem could lie in the connector itself and in its wiring.
Generally, the repair that most often cleans up this code is as follows:
- Replacing or repairing wiring damaged by overheating.
- Heated Oxygen Sensor (HO2S) Replacement
It should also be borne in mind that cars with a mileage of more than 100 km may have problems with sensors, especially at the starting stages and in stressful situations. This is often due to wear and tear associated with time and the high number of kilometers traveled by the vehicle.
It is not recommended to drive a car with a P0031 DTC, as the engine may fail while driving, possibly even stalling. In addition to the increase in fuel consumption that can be experienced over time, there is also a real risk of damage to the sensor circuit.
Due to the complexity of the inspections and interventions to be carried out, the DIY option in the home garage is absolutely not feasible.
It is difficult to estimate the upcoming costs, since a lot depends on the results of the diagnostics carried out by the mechanic. Typically, the cost of replacing a heated oxygen sensor, depending on the model, can range from 40 to 250 euros.
Frequently Asked Questions (FAQ)
What does code P0031 mean?
DTC P0031 logs a heated oxygen sensor malfunction.
What causes the P0031 code?
The most common causes of this code being triggered are a faulty oxygen sensor and a problem with the electrical connections.
How to fix code P0031?
It is necessary to check the electrical connections and the oxygen sensor, replacing the defective parts.
Can code P0031 go away on its own?
In some cases, this error may disappear on its own. In any case, it would be good to check the oxygen sensor.
Can I drive with code P0031?
Driving a vehicle with DTC P0031 is possible, but not recommended, as the engine may fail while driving, possibly even stalling.
How much does it cost to fix code P0031?
The cost of replacing a heated oxygen sensor, depending on the model, can vary from 40 to 250 euros.
Need more help with your p0031 code?
If you still need help with DTC P0031, post a question in the comments below this article.
NOTE. This information is provided for informational purposes only. It is not intended to be used as a repair recommendation and we are not responsible for any action you take on any vehicle. All information on this site is protected by copyright.
3 comment
da
Mazda 3 1.6 code p0031 HO211 circuit out of rang low voltage. I replaced the sensor and the light didn't go away. How do I fix it?
Antonio Alvarez placeholder image
Good, I have the check engine light on in my car (Toyota Camry 2003,2.4, 132000L, 0031 miles, automatic) and when I put the computer it gives me the error PXNUMX that refers to the oxygen sensor, I already changed it and put it the original and the problem persists, I have already reviewed everything associated with it and it is still the same and the car uses a lot of gasoline, in advance if you can support me I would appreciate it, a cordial greeting to all
istvan Tôth
I have a 2006 Suzuki Ignis 4wd, I replaced the front ball sensor, the engine runs fine, only the check light is on. and on my body, the bug is fixed, which makes the sound come back again. My bank code p0031 goes away again, everything goes well by itself when I turn off the engine. He repeats his mistake and he has become a new ball-soda. He likes not knowing what he is doing.