WOMS
P code powertrain High severity

P087B Transmission Fluid Pressure Sensor/Switch 'B' Range/Performance Problem

The OBD2 code P087B indicates a problem with the transmission fluid pressure sensor or switch 'B', specifically related to its range or performance, suggesting that the sensor is not providing accurate readings or is...

Definition

The OBD2 code P087B indicates a problem with the transmission fluid pressure sensor or switch 'B', specifically related to its range or performance, suggesting that the sensor is not providing accurate readings or is malfunctioning

Common causes

  • Faulty transmission fluid pressure sensor/switch
  • Wiring issues or damaged connectors
  • Low transmission fluid level
  • Contaminated transmission fluid
  • Transmission control module (TCM) malfunction
  • Internal transmission problems
  • Faulty transmission solenoids
  • Poor electrical connections

Common misdiagnoses

  • Faulty transmission control module (TCM)
  • Incorrectly diagnosed transmission issues
  • Faulty transmission fluid pressure sensor
  • Wiring or connector issues
  • Low transmission fluid level
  • Faulty transmission solenoids
  • Engine control module (ECM) issues
  • Misinterpretation of other transmission codes

Troubleshooting steps

  1. 1. Check for Additional Codes

    Use an OBD-II scanner to check for any other related trouble codes. This can provide more context and help identify if there are other issues affecting the transmission

  2. 2. Inspect the Transmission Fluid

    Fluid Level: Check the transmission fluid level. Low fluid can cause pressure issues

  3. 3. Fluid Condition

    Inspect the fluid for contamination, burning smell, or discoloration. If the fluid is dirty or burnt, it may need to be changed

  4. 4. Fluid Type

    Ensure the correct type of transmission fluid is being used as specified by the manufacturer

  5. 5. Examine the Transmission Fluid Pressure Sensor/Switch

    Visual Inspection: Check the sensor and its wiring for any signs of damage, corrosion, or loose connections

  6. 6. Connector Check

    Ensure that the electrical connector is secure and free of dirt or moisture

  7. 7. Test the Transmission Fluid Pressure Sensor

    Use a multimeter to test the sensor's resistance and voltage output according to the manufacturer’s specifications. Compare the readings to the expected values

  8. 8. If the sensor is faulty, it may need to be replaced

  9. 9. Check for Wiring Issues

    Inspect the wiring harness for any signs of wear, fraying, or short circuits. Pay special attention to areas where the wiring may be exposed to heat or moving parts

  10. 10. Inspect the Transmission Control Module (TCM)

    Ensure that the TCM is functioning properly. A malfunctioning TCM can lead to incorrect readings and performance issues

  11. 11. Check for any software updates or reprogramming that may be required

  12. 12. Look for Mechanical Issues

    Inspect the transmission for any mechanical problems that could affect fluid pressure, such as a stuck valve or internal leaks

  13. 13. If necessary, perform a pressure test on the transmission to ensure it is operating within the specified range

  14. 14. Clear Codes and Test Drive

    After performing the above checks and repairs, clear the trouble codes using the OBD-II scanner

  15. 15. Take the vehicle for a test drive to see if the code reappears. Monitor the transmission performance during the drive

  16. 16. Consult Technical Service Bulletins (TSBs)

    Check for any TSBs related to the specific make and model of the vehicle. Manufacturers may have issued guidance on common issues related to the P087B code

  17. 17. Seek Professional Help

    If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or transmission specialist for further diagnosis. By following these troubleshooting steps, you can systematically identify and address the underlying cause of the P087B code