P code powertrain Medium severity

P1724 Gear 4 Incorrect Ratio

The OBD2 code P1724 indicates that the transmission control module has detected an incorrect gear ratio in fourth gear, suggesting a potential issue with the transmission or related components

Definition

The OBD2 code P1724 indicates that the transmission control module has detected an incorrect gear ratio in fourth gear, suggesting a potential issue with the transmission or related components

Common causes

  • Faulty transmission control module (TCM)
  • Worn or damaged transmission components
  • Incorrect transmission fluid level or type
  • Malfunctioning speed sensors
  • Faulty shift solenoids
  • Electrical issues or wiring problems
  • Transmission fluid leaks
  • Incorrectly calibrated transmission system

Common misdiagnoses

  • Transmission fluid issues
  • Faulty speed sensors
  • Incorrectly calibrated transmission control module (TCM)
  • Worn or damaged transmission components
  • Engine control module (ECM) problems
  • Electrical connection issues
  • Incorrect tire size or pressure
  • Faulty throttle position sensor (TPS)

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 Transmission Fluid

    Check the transmission fluid level and condition. Low or dirty fluid can cause shifting issues. If the fluid is low, top it off with the manufacturer-recommended fluid. If it’s dirty or burnt, consider a transmission fluid change

  3. 3. Examine Wiring and Connectors

    Inspect the wiring and connectors related to the transmission and speed sensors. Look for signs of damage, corrosion, or loose connections that could affect sensor readings

  4. 4. Test the Vehicle Speed Sensor (VSS)

    The VSS provides information about the vehicle's speed to the ECM. Use a multimeter to test the sensor's output. If the sensor is faulty, it may need to be replaced

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

    If the vehicle has a separate TCM, ensure it is functioning correctly. Check for any software updates or reprogramming that may be needed

  6. 6. Inspect the Transmission

    If the above steps do not resolve the issue, there may be internal problems with the transmission, such as worn gears or clutches. A thorough inspection by a qualified technician may be necessary

  7. 7. Perform a Road Test

    After addressing any issues found, perform a road test to see if the code returns. Pay attention to how the transmission shifts, especially into fourth gear

  8. 8. Clear the Codes

    After repairs, clear the trouble codes using the OBD-II scanner and monitor the vehicle to see if the P1724 code reappears

  9. 9. Consult a Professional

    If the problem persists after performing these steps, it may be best to consult a professional mechanic or transmission specialist for further diagnosis and repair.Additional Considerations

  10. 10. Software Updates

    Sometimes, manufacturers release software updates that can resolve transmission-related issues. Check with the dealership for any available updates

  11. 11. Transmission Rebuild or Replacement

    In cases of severe internal damage, a rebuild or replacement of the transmission may be necessary. By following these troubleshooting steps, you can systematically identify and address the cause of the P1724 code