P2250 OBD-II Trouble Code: O2 Sensor Ref Voltage Circuit High Bank 2 Sensor 1

Our certified mechanics come to you · Get a fair and transparent estimate upfront


Cost of diagnosing the P2250 code

P2250 is a diagnostic trouble code (DTC) for "O2 Sensor Ref Voltage Circuit High Bank 2 Sensor 1". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic for $154.99 . Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $50.0 off as a credit towards the repair. All our repairs are backed by our 12-month / 12,000-mile warranty.

Cars Estimate* Credit towards follow-up repair Earliest Availability
Ford $154.99 $50.0
Toyota $154.99 $50.0
BMW $164.99 $50.0

*Estimates may vary by market

SCHEDULE P2250 DIAGNOSTIC Get a fair and transparent estimate upfront

P2250 code definition

The P2250 trouble code detects an issue with the upstream oxygen sensor voltage circuit in bank 2.

What the P2250 code means

The P2250 code is a generic OBD-II trouble code that suggests a problem with oxygen sensor 1 in bank 2. Bank 2 means that the issue is in the second engine bank, which is the bank that does not house the #1 cylinder. Sensor 1 means that the oxygen sensor is the upstream sensor, which is the one in front of the catalytic converter. The upstream sensor sends voltage information to the powertrain control module (PCM). When the heater circuit voltage varies from the battery voltage by more than 10 percent, or when the resistance level is more than 10 percent off of the standard 8 ohms, then the P2250 trouble code will be triggered.

What causes the P2250 code?

There are many potential causes for the P2250 trouble code, including:

  • Defective upstream oxygen sensor
  • Blow oxygen sensor fuse
  • Engine vacuum leak
  • Drastic exhaust leak
  • Fuel pressure that is very high or very low
  • In rare cases, a defective PCM
  • Malfunctioning or damaged oxygen sensor electrical connectors, wires, and harnesses

What are the symptoms of the P2250 code?

The P2250 trouble code will usually be accompanied by the Check Engine Light, which will illuminate on the instrument cluster. It is also common for the engine to run too lean or too rich, and the fuel efficiency to be lowered. Black smoke emitting from the tailpipe is also common.

How does a mechanic diagnose the P2250 code?

The P2250 code should be diagnosed with a standard OBD-II trouble code scanner. A trustworthy mechanic will use the scanner to view the freeze frame data and analyze the P2250 code. The technician will also look for any other trouble codes that are present. The codes should then be reset, and the vehicle restarted and taken for a short test drive. If the code does not return, then the issue was erroneously detected, or is an intermittent problem.

If the P2250 code returns, the mechanic should visually inspect the upstream oxygen sensor electrical components. All of the harnesses, wires, connectors, and fuses should be inspected, and any that are damaged or malfunctioning should be replaced.

Next, the technician will inspect the upstream oxygen sensor. In many vehicles, the sensor is easily removable, which makes inspection quicker and more thorough. If no issue has been detected after this point, the mechanic will begin a more thorough inspection, to check for exhaust leaks, vacuum leaks, and PCM failures.

Whenever a component is replaced, the trouble codes should be reset and the vehicle restarted to see if the issue has been resolved.

Common mistakes when diagnosing the P2250 code

The most commonly made mistake when diagnosing the P2250 code comes from a failure to properly follow the OBD-II trouble code diagnosis protocol. The protocol should always be followed strictly, to ensure that components are addressed in the right order. This ensures an efficient inspection and repair.

Failure to follow the proper protocol often results in replacing the upstream oxygen sensor when the issue is simple an electrical component.

How serious is the P2250 code?

If the P2250 code has been detected, the vehicle is still drivable. However, the car will likely get decrease fuel efficiency, and the engine may not run as well as it should. Failure to address the issue can result in damage to the engine, so the P2250 code should be handled as soon as possible.

What repairs can fix the P2250 code?

Some repairs for the P2250 trouble code include:

Additional comments for consideration regarding the P2250 code

It is very rare for a defective PCM to be the problem that causes the P2250 code to be detected. All other options should be checked before it is assumed that the PCM is malfunctioning. If the PCM needs to be replaced, it will also need to be reprogrammed.

Need help with a P2250 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.

Check Engine Light
trouble codes
P2250

No more waiting rooms! Our mechanics will come to you to diagnose and fix the P2250 code.

SCHEDULE P2250 DIAGNOSTIC
Get a $50 credit for the follow-up repair

Recent Check Engine Light is on Inspection reviews

Excellent Rating

(8600)

Rating Summary
8017
273
65
46
199
8017
273
65
46
199
 at YourMechanic

Brandon

9 years of experience
133 reviews
Brandon
9 years of experience
Ford Escort L4-2.0L - Check Engine Light is on - Nashville, Tennessee
Brandon showed up ahead of schedule, was very personable and diagnosed my problems. He also scheduled my next appointments which will be with him.
 at YourMechanic

William

23 years of experience
33 reviews
William
23 years of experience
Lexus IS250 V6-2.5L - Check Engine Light is on - Mableton, Georgia
Arrived early which was great. William was courteous, and attentive to the issue. Even though it took several attempts I'm so happy he was determined to fix it and he did!
 at YourMechanic

Dan

40 years of experience
1080 reviews
Dan
40 years of experience
Plymouth Grand Voyager - Check Engine Light is on - Lawrenceville, Georgia
Mr. Dan Barber was quite patient, courteous and quite knowledgeable. From my observation, Mr. Barber appears to be quite professional.
 at YourMechanic

Christopher

9 years of experience
120 reviews
Christopher
9 years of experience
Ford Fiesta L4-1.6L - Check Engine Light is on - Smyrna, Georgia
Chris communicated with us each step of the way up until his arrival. He listened well, was knowledgeable, and was prepared. He took the time to diagnose the problem, explained the what, why and how and provided a solution. I would definitely recommend him and will use him again.


More related articles

P2066 OBD-II Trouble Code: Fuel Level Sensor “B” Performance
P2066 P2066 code definition Fuel Level Sensor “B” Performance What the P2066 code means P2066 is an OBD-II generic code for the engine control module (ECM) detecting the fuel level sensor “B” performance. The sensor output voltage is not accurate...
P2425 OBD-II Trouble Code: Exhaust Gas Recirculation Cooling Valve Control Circuit Open
P2425 P2425 code definition Exhaust Gas Recirculation Cooling Valve Control Circuit Open What the P2425 code means P2425 is an OBD-II generic code that the engine control module (ECM) detected the engine exhaust gas recirculation cooling bypass valve (EGRCBV) control...
P0363 OBD-II Trouble Code: Misfire Detected - Fueling Disabled
P0363 P0363 code definition If the PCM has stored the P0363 code, it indicates that there has been a misfire in a cylinder, and that the PCM has disabled the fuel supply to the malfunctioning cylinder. What the P0363 code...

Related questions

Check Engine light is not on
The catalyst inside of the converter can break away and cause rattling noises in the exhaust, especially on acceleration. Over time the catalyst material can break apart and cause partial plugging of the exhaust. If the catalyst is no longer...
P0302 code/CEL. Spark plugs could be cause but not sure
This code relates to a misfire which may be caused by many different reasons. This may be caused by faulty spark plug wires or plugs, a faulty coil pack, faulty O2 sensors or potentially a dirty or clogged fuel injector....
Blinking Check Engine Light
As you may know, the Check Engine Light can come on for many different reasons, including for the ignition coils (https://www.yourmechanic.com/services/ignition-coil-replacement) being faulty. Many times, when there are no visible signs or obvious symptoms of the car running poorly, it...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (844) 997-3624 · hi@yourmechanic.com