P2172: Throttle/Pedal Position Sensor/Switch 'D' Circuit Range/Performance Problem

Definition

The OBD2 code P2172 indicates a problem with the throttle or pedal position sensor/switch 'D', specifically related to its range or performance, suggesting that the sensor is not functioning within the expected parameters

Common causes

Faulty throttle position sensor (TPS)
Faulty accelerator pedal position sensor
Wiring issues (shorts, opens, or corrosion)
Poor electrical connections
Throttle body issues (carbon buildup or mechanical failure)
Faulty engine control module (ECM)
Software issues or calibration problems
Vacuum leaks in the intake system
Malfunctioning cruise control system (if equipped)

Common misdiagnoses

Faulty throttle body
Bad accelerator pedal position sensor
Wiring issues or poor connections
Vacuum leaks
Engine control module (ECM) problems
Incorrectly calibrated throttle position sensor
Faulty mass air flow sensor
Fuel delivery issues
Ignition system problems
Transmission issues

Troubleshooting steps

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. Inspect Throttle Body and Pedal Position Sensor
3. Visually inspect the throttle body and the pedal position sensor for any signs of damage, dirt, or carbon buildup. Clean the throttle body if necessary
4. Check the wiring and connectors for any signs of wear, corrosion, or loose connections
5. Test the Throttle Position Sensor (TPS)
6. Use a multimeter to test the TPS for proper voltage and resistance. Compare the readings to the manufacturer's specifications
7. Check for smooth operation throughout the entire range of motion
8. Check the Accelerator Pedal Position Sensor
9. Similar to the TPS, test the accelerator pedal position sensor for proper voltage and resistance
10. Ensure that the sensor is functioning correctly and that there are no dead spots in its range
11. Inspect the Wiring and Connectors
12. Look for damaged wiring, frayed wires, or poor connections in the throttle and pedal position sensor circuits
13. Repair or replace any damaged components as necessary
14. Check for Vacuum Leaks
15. Inspect the intake system for any vacuum leaks that could affect the throttle position readings. Use a smoke machine or spray soapy water to identify leaks
16. Perform a Throttle Body Relearn
17. If the throttle body has been cleaned or replaced, perform a throttle body relearn procedure as per the vehicle manufacturer’s specifications. This can help recalibrate the throttle position
18. Inspect the Engine Control Module (ECM)
19. In rare cases, the ECM may be faulty. Check for any software updates or recalls related to the ECM
20. If all other components check out, consider testing or replacing the ECM
21. Test Drive the Vehicle
22. After performing the above checks and repairs, clear the trouble codes and take the vehicle for a test drive to see if the code returns
23. Consult Repair Manual
24. Refer to the vehicle’s service manual for specific diagnostic procedures and specifications related to the throttle and pedal position sensors. If the issue persists after following these steps, it may be advisable to consult a professional mechanic for further diagnosis and repair

Definition

Common causes

Common misdiagnoses

Troubleshooting steps

1. Check for Additional Codes

2. Inspect Throttle Body and Pedal Position Sensor

3. Visually inspect the throttle body and the pedal position sensor for any signs of damage, dirt, or carbon buildup. Clean the throttle body if necessary

4. Check the wiring and connectors for any signs of wear, corrosion, or loose connections

5. Test the Throttle Position Sensor (TPS)

6. Use a multimeter to test the TPS for proper voltage and resistance. Compare the readings to the manufacturer's specifications

7. Check for smooth operation throughout the entire range of motion

8. Check the Accelerator Pedal Position Sensor

9. Similar to the TPS, test the accelerator pedal position sensor for proper voltage and resistance

10. Ensure that the sensor is functioning correctly and that there are no dead spots in its range

11. Inspect the Wiring and Connectors

12. Look for damaged wiring, frayed wires, or poor connections in the throttle and pedal position sensor circuits

13. Repair or replace any damaged components as necessary

14. Check for Vacuum Leaks

15. Inspect the intake system for any vacuum leaks that could affect the throttle position readings. Use a smoke machine or spray soapy water to identify leaks

16. Perform a Throttle Body Relearn

17. If the throttle body has been cleaned or replaced, perform a throttle body relearn procedure as per the vehicle manufacturer’s specifications. This can help recalibrate the throttle position

18. Inspect the Engine Control Module (ECM)

19. In rare cases, the ECM may be faulty. Check for any software updates or recalls related to the ECM

20. If all other components check out, consider testing or replacing the ECM

21. Test Drive the Vehicle

22. After performing the above checks and repairs, clear the trouble codes and take the vehicle for a test drive to see if the code returns

23. Consult Repair Manual

24. Refer to the vehicle’s service manual for specific diagnostic procedures and specifications related to the throttle and pedal position sensors. If the issue persists after following these steps, it may be advisable to consult a professional mechanic for further diagnosis and repair