Error Code P0122
Moderate Issue
DTC Code P0122 indicates a low voltage issue in the Throttle Position Sensor 1 Circuit. This occurs when the Engine Control Module (ECM) detects that the throttle position sensor 1 signal voltage is below 0.32 V for more than 1 second, affecting the communication from the throttle body to the ECM.
What symptoms indicate Error Code P0122?
- Engine Light ON: The check engine light or service engine soon warning light illuminates, indicating a potential issue with the throttle position sensor circuit.
- Poor Acceleration: The vehicle may experience sluggish or unresponsive acceleration due to incorrect throttle position readings.
- Stalling or Hesitation: The engine might stall or hesitate during acceleration, as the throttle position sensor fails to provide accurate data.
- Rough Idle: The engine may idle roughly or inconsistently, as the throttle position sensor affects the air-fuel mixture.
What causes OBD code Error Code P0122?
- The throttle body assembly may be malfunctioning, leading to incorrect voltage readings from the throttle position sensor.
- An open or shorted harness in the throttle body assembly can disrupt the electrical signal, causing low voltage issues.
- Poor electrical connections in the throttle body assembly circuit can result in intermittent or weak signals to the ECM.
- A faulty Engine Control Module (ECM) might not process the throttle position sensor signals correctly, leading to erroneous low voltage readings.
How to fix OBD code Error Code P0122?
- Initial Inspection: Inspect the throttle position sensor (TPS) and its wiring for any visible damage or disconnection. Ensure the connectors are secure and free from corrosion.
- Check Voltage Supply: Using a multimeter, measure the voltage at the TPS connector. The reference voltage should be around 5 volts. A lower voltage indicates a potential issue with the power supply or wiring.
- Test TPS Signal: With the ignition on, back-probe the signal wire of the TPS and measure the voltage. It should vary smoothly from approximately 0.5 volts at closed throttle to about 4.5 volts at wide open throttle. Any irregularities suggest a faulty sensor.
- Inspect Ground Circuit: Verify the ground circuit of the TPS using a multimeter. A poor ground can cause low voltage readings. Ensure the ground connection is clean and secure.
- Scan for Related Codes: Check for any additional DTCs related to the throttle position sensor or circuit. This can provide further insight into the issue and help pinpoint the problem.
- Perform Throttle Body Inspection: Inspect the throttle body for any obstructions or carbon build-up that may affect the sensor's operation. Clean if necessary.
- Replace TPS if Necessary: If all tests indicate a faulty TPS, replace the sensor and clear the DTC code. Re-test to ensure the issue is resolved.