P2122
DTC P2120 Throttle / Pedal Position Sensor / Switch "D" CircuitDTC P2122 Throttle / Pedal Position Sensor / Switch "D" Circuit Low Input
DTC P2123 Throttle / Pedal Position Sensor / Switch "D" Circuit High Input
DTC P2125 Throttle / Pedal Position Sensor / Switch "E" Circuit
DTC P2127 Throttle / Pedal Position Sensor / Switch "E" Circuit Low Input
DTC P2128 Throttle / Pedal Position Sensor / Switch "E" Circuit High Input
DTC P2138 Throttle / Pedal Position Sensor / Switch "D" / "E" Voltage Correlation
HINT: These DTCs relate to the Accelerator Pedal Position (APP) sensor.
DTC Detection Condition:
DESCRIPTION
HINT:
- This accelerator pedal position sensor is a non-contact type.
- This ETCS (Electronic Throttle Control System) does not use a throttle cable.
The Accelerator Pedal Position (APP) sensor is mounted on the accelerator pedal bracket and has 2 sensor circuits: VPA1 (main) and VPA2 (sub). The voltage, which is applied to terminals VPA1 and VPA2 of the ECM, varies between 0 V and 5 V in proportion to the operating angle of the accelerator pedal (throttle valve). A signal from VPA1 indicates the actual accelerator pedal opening angle (throttle valve opening angle) and is used for engine control. A signal from VPA2 conveys the status of the VPA1 circuit and is used to check the APP sensor itself.
The ECM monitors the actual accelerator pedal opening angle (throttle valve opening angle) through the signals from VPA1 and VPA2, and controls the throttle actuator according to these signals.
HINT: After confirming DTC P2120, P2122, P2123, P2125, P2127, P2128 and P2138, use the intelligent tester or the OBD II scan tool to confirm the throttle valve opening percentage.
HINT:
- Accelerator pedal positions are expressed as voltages.
- AP stands for Accelerator Pedal.
MONITOR DESCRIPTION
Monitor Strategy:
Typical Enabling Conditions:
Typical Malfunction Thresholds (Part 1):
Typical Malfunction Thresholds (Part 2):
Component Operating Range:
When VPA or VPA2 deviates from the standard, or the difference between the voltage outputs of the two sensors is less than threshold, the ECM concludes that there is a defect in the accelerator pedal position sensor. The ECM turns on the MIL and a DTC is set.
Example: When the voltage output of the VPA is below 0.2 V or exceeds 4.8 V.
FAIL-SAFE
The accelerator pedal position sensor has two (main and sub) sensor circuits. If a malfunction occurs in either of the sensor circuits, the ECM detects the abnormal signal voltage difference between the two sensor circuits and switches to limp mode. In limp mode, the remaining circuit is used to calculate the accelerator pedal opening to allow the vehicle to continue driving.
If both circuits malfunction, the ECM regards the opening angle of the accelerator pedal to be fully closed. In this case, the throttle valve will remain closed as if the engine is idling.
If a "pass-condition is detected and then the ignition switch is turned OFF, the fail-safe operation will stop and the system will return to normal condition.
Wiring Diagram:
Step 1:
Step 2:
Step 3-5:
Step 5(Continued):
INSPECTION PROCEDURE
HINT: Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air/fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.