Fault code P0152 is called “O₂ Sensor Circuit High Voltage (Bank 2, Sensor 1)” but in different programs it may be called differently. This fault designation applies to all vehicles equipped with OBD-II.
Technical description and explained code P0152
This Diagnostic Trouble Code (DTC) is a general powertrain code. Error P0152 is considered a general code because it applies to all makes and models of vehicles. Although the specific repair steps may vary slightly depending on the model.
The O₂ (oxygen) sensors basically measure the oxygen content of the exhaust gases. The PCM (transmission control module) then uses this information to adjust the fuel injector pulse.
They are very important to the proper operation of the engine. Problems with them can cause the PCM to add or take too much fuel because of a faulty O₂ sensor voltage.
The O₂ sensor gives off voltage depending on the oxygen content of the exhaust. It may vary from 0.1 to 0.9 volts. Where 0.1 indicates lean exhaust and 0.9 indicates rich exhaust.
This problem indicates that the O₂ sensor is hovering above 0.9 volts. PCM monitors this voltage and if it detects that the voltage is too high. It writes the error into the memory and sets the code P0152.
Symptoms of vehicle malfunctions
The main signal that an error P0152 has occurred is the Malfunction Indicator Lamp (MIL) is also known as the CheckEngine Light.
It can also be warning signs such as:
- Check engine control lamp on the control panel will light up (the code will be recorded in the ECM memory as a fault).
- Ignition skips in the engine cylinders may occur. Also the vehicle’s engine may run erratically.
- The engine may run on lean or rich mixture, depending on whether the O₂ sensor indicates correctly or not.
- Reduced power and traction.
- Increased fuel consumption.
Failure of the oxygen sensor can result in the vehicle’s ECM not being able to adjust the air-fuel mix ratio properly. This can result in increased fuel consumption and damage to engine parts. Therefore, it is recommended that fault P0152 be corrected as soon as possible.
Factors that can cause this error code
The error code P0152 can mean that one or more of the following problems have occurred:
- Defective oxygen sensor O₂ Bank 2 sensor 1 does not read rich mixture correctly.
- O₂ sensor causes the engine to run on rich mixture.
- The signal is shorted in the wiring harness.
- Damage/melting of the wiring harness due to contact with parts of the exhaust system.
- Leaking injectors.
- Bad fuel pressure regulator.
- Trouble with PCM unit.
How to fix or reset OBD-2 code P0152
Some suggested steps for troubleshooting and fix the error code P0152:
- Read all stored data and error codes with an OBD-II scanner. Clear the error codes from the computer memory and test-drive the vehicle. To find out if code P0152 appears again.
- Observe the oxygen sensor data in real time using the scan tool. To find out if the sensor voltage is 0.9 volts or more.
- Check and, if necessary, replace the oxygen sensor electrical leads or connector.
Diagnose and repair of problems
If there are any other codes, you should focus on correcting them first. Because they may cause the voltage reading of the O₂ sensor to seem wrong. But they will actually read correctly.
With the engine running and at operating temperature, use a diagnostic tool to observe the voltage reading of sensor O₂ bank 2 of sensor 1. If the sensor is triggered, there is most likely a problem with the engine, not the sensor.
If the O₂ sensor reading remains high (0.9 V or higher) and does not respond, turn off the engine. Disconnect the sensor and inspect for corrosion or water intrusion. Repair if necessary. The voltage reading should now be about 0.5 V. If not, replace the sensor, it is shorted internally.
The voltage reading on the diagnostic scanner, after disconnecting the sensor does not change, then most likely there is a problem with the wiring. Inspect the harness, look for any melted wires or places where the sensor harness is in contact with exhaust system components.
If you’re not sure, you can check the continuity of all four wires between the sensor and PCM with an ohmmeter. Repair if necessary.
On which vehicles does this problem occur most frequently
Fault code P0152 can occur on different vehicles but there are statistics on which brands this occurs most often. Here is a list of some of them:
- BMW
- Chevrolet (Captiva)
- Chrysler
- Dodge (Caravan, Durango, Intrepid, RAM)
- Honda
- Hyundai
- Jeep (Grand Cherokee)
- Mitsubishi
- Nissan (350Z)
- Toyota
- Volvo
Fault code P0152 can sometimes be found with other errors. The most common are the following: P0050, P0051, P0130, P0132, P0134, P0136, P0139, P0141, P0155, P0158, P0161, P0171, P0174, P0299, P0300, P0700, P0870, P1491, P1615.
