WOMS
P code powertrain Medium severity

P0904 Gate Select Position Circuit [senses left / right position]

The OBD2 code P0904 indicates a malfunction in the gate select position circuit, which senses the left or right position of the gear selector in a vehicle's transmission system

Definition

The OBD2 code P0904 indicates a malfunction in the gate select position circuit, which senses the left or right position of the gear selector in a vehicle's transmission system

Common causes

  • Faulty gate select position sensor
  • Damaged wiring or connectors
  • Poor electrical connections
  • Malfunctioning transmission control module (TCM)
  • Mechanical issues in the gate select mechanism
  • Corrosion or dirt in the sensor or connectors
  • Software issues or glitches in the vehicle's control system

Common misdiagnoses

  • Transmission control module (TCM) failure
  • Faulty gate select switch
  • Wiring issues or shorts in the circuit
  • Incorrectly calibrated transmission
  • Faulty transmission range sensor
  • Malfunctioning gear selector assembly
  • Issues with the vehicle's body control module (BCM)

Troubleshooting steps

  1. 1. Check for Additional Codes

    Use an OBD-II scanner to check for any other trouble codes that may be present. This can provide more context and help identify related issues

  2. 2. Inspect Wiring and Connectors

    Visually inspect the wiring and connectors associated with the gate select position sensor. Look for signs of damage, corrosion, loose connections, or frayed wires. Repair or replace any damaged components

  3. 3. Test the Gate Select Position Sensor

    Use a multimeter to test the resistance and voltage output of the gate select position sensor. Compare the readings to the manufacturer's specifications. If the sensor is out of spec, it may need to be replaced

  4. 4. Check the Transmission Control Module (TCM)

    Ensure that the TCM is functioning properly. Sometimes, a software update or reprogramming may be necessary. Check for any known issues or recalls related to the TCM for your specific vehicle model

  5. 5. Inspect the Gear Selector Mechanism

    Check the gear selector mechanism for proper operation. Ensure that it is not binding or obstructed, which could affect the position sensing

  6. 6. Clear the Codes and Test Drive

    After performing any repairs or adjustments, clear the trouble codes using the OBD-II scanner and take the vehicle for a test drive to see if the code returns

  7. 7. Consult Technical Service Bulletins (TSBs)

    Look for any TSBs related to the P0904 code for your specific vehicle make and model. Manufacturers may have issued guidance on common issues and fixes

  8. 8. Seek Professional Help

    If the issue persists after performing the above steps, it may be necessary to consult a professional mechanic or technician who has experience with your vehicle's transmission system. By following these troubleshooting steps, you can systematically identify and resolve the issue associated with the P0904 code