Advanced Diagnostics

Advanced Diagnostics

DTC P0122: Throttle Position (TP) Sensor A Circuit Low Voltage






General Description
The electronic throttle control system (ETCS) controls the throttle valve opening. The system is composed of the throttle actuator, the throttle valve, throttle position (TP) sensors A and B, the accelerator pedal position (APP) sensor, and the engine control module (ECM)/powertrain control module (PCM). Throttle position (TP) sensor A is a semiconductor type, and it is attached to the throttle body and shaft to determine throttle valve position. The throttle valve position signal from TP sensor A is transmitted to the ECM/PCM for target position feedback control. If the signal from TP sensor A is less than a fixed value for a set time, the ECM/PCM detects a TP sensor A malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type, OBD Status






Enable Conditions






Malfunction Threshold
The TP sensor A output voltage is 0.3 V or less for at least 200 milliseconds.

Diagnosis Details

Conditions for illuminating the MIL
When a malfunction is detected, the MIL comes on and the DTC and the freeze frame data are stored in the ECM/PCM memory.

Conditions for clearing the MIL
The MIL will be cleared if the malfunction does not recur during three consecutive trips in which the diagnostic runs. The MIL, the DTC, and the freeze frame data can be cleared by using the scan tool Clear command or by disconnecting the battery.