P2123Throttle/Pedal Position Sensor/Switch "D" Circuit High
The OBD2 code P2123 indicates that the Throttle/Pedal Position Sensor or switch "D" is sending a high voltage signal, which may suggest a malfunction or an issue in the sensor circuit
Definition
Common causes
- Faulty throttle position sensor
- Damaged wiring or connectors
- Short circuit in the throttle position sensor circuit
- Corroded connectors
- Faulty engine control module (ECM)
- Poor ground connection
- Mechanical issues with the throttle body
Common misdiagnoses
- Throttle body issues
- Accelerator pedal assembly failure
- Wiring or connector problems
- Engine control module (ECM) failure
- Other throttle position sensor malfunctions
- Vacuum leaks
- Fuel system issues
- Ignition system problems
Troubleshooting steps
1.Check for Additional Codes
Use an OBD-II scanner to check for any other related trouble codes. This can provide more context and help identify if there are multiple issues
2.Inspect the Throttle Position Sensor (TPS)
Locate the throttle position sensor and visually inspect it for any signs of damage, corrosion, or loose connections
3.Ensure that the wiring harness and connectors are secure and free from dirt or moisture
4.Test the Throttle Position Sensor
Use a multimeter to test the resistance and voltage output of the TPS. Compare the readings to the manufacturer's specifications
5.Check for proper operation by moving the throttle plate and observing the sensor's output
6.Check the Wiring and Connectors
Inspect the wiring leading to the TPS for any signs of wear, fraying, or short circuits
7.Ensure that all connectors are clean, tight, and free from corrosion
8.Inspect the Accelerator Pedal Position Sensor
If applicable, check the accelerator pedal position sensor, as it may also be related to the throttle control system
9.Perform similar tests as with the TPS to ensure it is functioning correctly
10.Check for Ground Issues
Ensure that the ground connections for the throttle position sensor and related components are secure and free from corrosion
11.Examine the Engine Control Module (ECM)
If all other components check out, there may be an issue with the ECM itself. Check for software updates or reprogramming if necessary
12.Clear the Codes and Test Drive
After performing 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
13.Consult Technical Service Bulletins (TSBs)
Check for any TSBs related to the P2123 code for your specific vehicle make and model, as there may be known issues or recalls
14.Seek Professional Help
If the issue persists after performing these steps, it may be best to consult a professional mechanic or technician for further diagnosis. By following these troubleshooting steps, you can systematically identify and resolve the issue associated with the P2123 code