Skip the auto shop - Our mechanics make house calls

P2631 OBD-II Trouble Code: O2 Sensor Pumping Current Trim Circuit High Bank 2 Sensor 1

Check Engine Light

What the P2631 code means?

P2631 is an OBD-II generic code for the engine control module (ECM) detecting an open or short circuit in the Air Fuel Radio (A/F) or O2 sensor, causing a high voltage at the signal wire to the ECM.

What causes the P2631 code?

  • The ECM monitors the A/F or O2 sensor signal wire voltage and will set the code of higher voltage than expected is seen.

  • The O2 sensor signal return wire shorted to the 5 volt reference wire.

What are the symptoms of the P2631 code?

  • The Check Engine light will be illuminated and the code is set in ECM memory as a fault.

  • The engine may not be able to go into closed fuel loop and will go into failure mode fuel control.

  • The engine may run good but may have very minor drivability symptoms like hesitation or lowered fuel mileage.

How does a mechanic diagnose the P2631 code?

  • Scans for codes and documents the code in the ECM and looks at the freeze frame data for failure.

  • Checks the O2 sensor and wiring harness for cuts into the harness causing the short.

  • Tests the wiring and sensor for shorted or corroded connectors and wiring.

  • Scans the O2 sensors and checks the voltage return on the signal wire for short to reference voltage.

Common mistakes when diagnosing the P2631 code?

  • Clearing ECM memory codes before checking the freeze frame data for the main failure problem, so the failure may be duplicated and repaired

  • Replacing the A/F or O2 sensor without checking the wiring connector for short to reference voltage

How serious is the P2631 code?

Code P2631 is a code indicating the A/F O2 sensor return signal is shorted to power and cannot generate the correct signal to the ECM for fuel control. The engine will not run in closed loop as long as the problem is happening.

What repairs can fix the P2631 code?

Additional comments for consideration regarding the P2631 code

Code P2631 is caused most commonly from an internal short to reference voltage in the A/F or O2 sensor. The sensor can be called an A/F sensor or an O2 sensor depending on manufacturer.

Need help with a P2631 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
How to Buy Fuel Treatments
Adding a fuel additive to your gas tank when you fill up is one way to clean vital engine parts of deposits, improve the performance of your engine,...
Insurance Requirements for Car Registration in Kentucky
The Kentucky Transportation Cabinet requires that all drivers in Kentucky carry liability automotive insurance, or “financial responsibility” in order to operate a vehicle legally and maintain vehicle...


Related questions

Q: My VSA light keeps coming on. And my brake Padal feels weird when you know the light is going to come. Is this something major ?

Hi there. It is possible that this is something that you should be concerned with. It can be low brake fluid or it may be a wheel speed sensor problem. If you have different tires then this will also occur....

Q: Engine knock and hesitation

The poor acceleration and misfiring can definitely be tied to the[clogged catalytic converter, but something had to clog the converter. In many cases, oil entering the exhaust or too rich of an air/fuel mixture can overwork the catalytic converter to...

Q: Stalls when turning or at a stop

Hi there. The first step is to check for any problem codes stored by engine management. This can save a lot of time money when diagnosing drive-ability problems. Most auto parts stores will do this for free. Several problems could...