Skip the auto shop - Our mechanics make house calls
  1. Home
  2. Articles
  3. P0158 OBD-II Trouble Code: 02 Sensor Circuit High Voltage (Bank 2, Sensor 2)

P0158 OBD-II Trouble Code: 02 Sensor Circuit High Voltage (Bank 2, Sensor 2)

Check Engine Light

P0158 trouble code definition

Oxygen Sensor Circuit High Voltage (Bank 2 Sensor 2)

What the P0158 code means

The P0158 trouble code appears when the sensor has remained at a high voltage for too long.

This oxygen sensor is located behind the catalytic converter. It sends information to the power control module (PCM) about the efficiency and released oxygen levels of the catalytic converter.

When an engine is running lean, it means that there is more oxygen than fuel in the exhaust gases. When the engine is running rich, it means that there is more fuel than oxygen in the exhaust gases.

If the sensor is working properly it switches from low voltage (high levels of oxygen) to a high voltage (low levels of oxygen).

What causes the P0158 code?

  • Failed rear oxygen sensor
  • Failed rear oxygen sensor heater circuit
  • Engine coolant temperature sensor bad
  • Shorts, breaks, or exposed oxygen sensor wiring
  • Excessive fuel pressure
  • Necessary power control module (PCM) update
  • Failure of the power control module (PCM)

What are the symptoms of the P0158 code?

  • Check Engine Light will come on
  • Decreased fuel economy
  • Engine runs rough
  • Engine idles rough
  • Engine stalls

How does a mechanic diagnose the P0158 code?

  • A mechanic will use an OBD-II scanner to pull all present trouble codes that have been stored by the power control module (PCM).

  • The live data for the oxygen sensor on the scanner is reviewed. They will check the voltage reading to see if the oxygen sensor switches from low voltage to high voltage every few seconds.

  • When an engine coolant temperature sensor trouble code is present as well, the live data on the scanner is checked for proper engine temperature.

  • The wiring of the rear oxygen sensor is checked for shorts, breaks, or exposure.

  • Test the fuel pressure to see if it is higher than normal.

  • Run manufacturer diagnosis procedures on the power control module (PCM) to determine whether it needs to be replaced or updated.

Common mistakes when diagnosing the P0158 code

  • Replacing the oxygen sensor before considering other necessary repairs
  • Not properly expecting the wires for any shorts, breaks, or exposure

How serious is the P0158 code?

The P0158 trouble code is considered serious if it is causing the car to stall out. This problem should be addressed as soon as possible to avoid drivability issues.

What repairs can fix the P0158 code?

  • Replace the rear oxygen sensor
  • Repair any oxygen sensor wires that have shorted out, are broken or exposed
  • Make necessary repairs to remedy the excessive fuel pressure.
  • Replace engine coolant temperature sensor if it is necessary
  • Replace or update power control module (PCM), if necessary

Additional comments for consideration regarding the P0158 code

An oxygen sensor set and propane tank will be necessary to remove the oxygen sensor if it has ceased in the exhaust or is difficult to reach.

Need help with a P0158 code?

YourMechanic offers certified 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

How to Find the Keyless Code on a Ford Explorer or Mercury Mountaineer
Many Ford Explorers and Mercury Mountaineers were manufactured with an option known as the Ford keyless entry keypad. Some models refer to it as SecuriCode as well. It...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
The Traveler’s Guide to Driving in Malaysia
CraigBurrows / Shutterstock.com Malaysia is a popular destination for many tourists today. The country has amazing sights and attractions that you will want to explore....


Related questions

Q: Engine not reving past 2500 rpm

You will need to have the computer scanned for codes that caused the Check Engine Light to come on. Once the code is diagnosed then you will find out if the fuel is contaminated with water. You may have an...

Q: Getting Red Lighting Bolt Warning Light and Check Engine Light

Hi there. Assuming the Check Engine Light and red lightning bolt were on before your vehicle experienced the no start condition. This would indicate a malfunction in the electronic throttle control system. The computer has recognized the fault and stored...

Q: Car computer showing several fault codes.

I would have a technician tune the car up and replace the spark plugs and coil packs. That is the code for misfire and coil pack problems. Code p01297 is a code for the map sensor. You could have a...