WOMS
P code powertrain Medium severity

P0803 1-4 Upshift (Skip Shift) Solenoid Control Circuit Malfunction

The OBD2 code P0803 indicates a malfunction in the control circuit of the 1-4 upshift (skip shift) solenoid, which is responsible for managing the transmission's shift patterns to improve fuel efficiency

Definition

The OBD2 code P0803 indicates a malfunction in the control circuit of the 1-4 upshift (skip shift) solenoid, which is responsible for managing the transmission's shift patterns to improve fuel efficiency

Common causes

  • Faulty skip shift solenoid
  • Wiring issues (shorts, opens, or corrosion)
  • Poor electrical connections
  • Failed transmission control module (TCM)
  • Faulty transmission range sensor
  • Low transmission fluid level or quality
  • Internal transmission issues

Common misdiagnoses

  • Faulty transmission control module (TCM)
  • Wiring issues or shorts in the solenoid circuit
  • Defective skip shift solenoid
  • Transmission fluid issues (low or contaminated fluid)
  • Faulty engine control module (ECM)
  • Incorrectly diagnosed transmission problems
  • Issues with the clutch or clutch actuator
  • Problems with the vehicle's speed sensors

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 skip shift solenoid. Look for signs of damage, corrosion, or loose connections

  3. 3. Ensure that the connectors are securely attached and that there are no broken wires

  4. 4. Test the Skip Shift Solenoid

    Locate the skip shift solenoid and test its resistance using a multimeter. Compare the readings to the specifications provided in the vehicle’s service manual

  5. 5. If the solenoid is out of specification, it may need to be replaced

  6. 6. Check the Transmission Fluid

    Ensure that the transmission fluid is at the correct level and is in good condition. Low or dirty fluid can affect transmission performance and solenoid operation

  7. 7. If the fluid is dirty, consider performing a transmission fluid change

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

    Check for any issues with the TCM, as it controls the operation of the solenoid. Look for signs of damage or corrosion

  9. 9. If necessary, test the TCM for proper operation

  10. 10. Perform a Visual Inspection of the Transmission

    Inspect the transmission for any signs of leaks or damage that could affect the solenoid's operation

  11. 11. Check for Ground Issues

    Ensure that the ground connections for the solenoid and TCM are secure and free of corrosion. Poor grounding can lead to circuit malfunctions

  12. 12. Clear the Codes and Test Drive

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

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

  14. 14. Consult a Professional

    If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or technician who has experience with transmission systems and OBD-II diagnostics. By following these troubleshooting steps, you can systematically identify and resolve the issue related to the P0803 code