WOMS
P code powertrain High severity

P0736 Reverse incorrect gear ratio

The OBD2 code P0736 indicates that the transmission control module has detected an incorrect gear ratio in reverse gear, suggesting a potential issue with the transmission or its components

Definition

The OBD2 code P0736 indicates that the transmission control module has detected an incorrect gear ratio in reverse gear, suggesting a potential issue with the transmission or its components

Common causes

  • Low transmission fluid level
  • Faulty transmission fluid pump
  • Worn or damaged transmission components
  • Malfunctioning valve body
  • Defective transmission control module (TCM)
  • Faulty input or output speed sensors
  • Electrical issues or wiring problems
  • Incorrectly installed or damaged torque converter
  • Transmission overheating
  • Software issues or updates needed in the TCM

Common misdiagnoses

  • Transmission fluid issues (low or dirty fluid)
  • Faulty transmission control module (TCM)
  • Worn or damaged transmission components
  • Incorrectly installed or malfunctioning valve body
  • Faulty speed sensors
  • Electrical issues (wiring or connectors)
  • Misdiagnosed engine problems affecting transmission performance
  • Incorrectly diagnosed torque converter issues

Troubleshooting steps

  1. 1. Check Transmission Fluid Level and Condition

  2. 2. Ensure that the transmission fluid is at the correct level. Low fluid can cause shifting issues

  3. 3. Inspect the fluid for contamination, burning smell, or dark color. If the fluid is dirty or burnt, consider a transmission fluid change

  4. 4. Inspect for Leaks

  5. 5. Look for any signs of transmission fluid leaks. Leaks can lead to low fluid levels and affect transmission performance

  6. 6. Scan for Additional Codes

  7. 7. Use an OBD-II scanner to check for any other related trouble codes. Other codes may provide additional context for the issue

  8. 8. Check Transmission Wiring and Connectors

  9. 9. Inspect the wiring and connectors related to the transmission for damage, corrosion, or loose connections. Electrical issues can affect transmission operation

  10. 10. Test the Transmission Range Sensor

  11. 11. The transmission range sensor (or neutral safety switch) tells the TCM what gear the transmission is in. If it’s malfunctioning, it can cause incorrect gear ratio readings

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

  13. 13. Check for any software updates or reprogramming that may be needed for the TCM. In some cases, a faulty TCM may need to be replaced

  14. 14. Check for Mechanical Issues

  15. 15. Inspect the transmission for internal mechanical issues, such as worn gears, clutches, or bands. A transmission rebuild or replacement may be necessary if internal damage is found

  16. 16. Perform a Transmission Fluid Flush

  17. 17. If the fluid is contaminated, a complete flush may help improve performance. However, this should be done with caution, as it can sometimes exacerbate existing issues

  18. 18. Road Test the Vehicle

  19. 19. After performing the above checks, take the vehicle for a test drive to see if the issue persists. Pay attention to how the transmission shifts, especially into reverse

  20. 20. Consult a Professional

  21. 21. 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. Always remember to follow safety precautions when working on vehicles, and if you're unsure about any step, it's best to seek professional assistance