P2125

DTC P2120 Throttle / Pedal Position Sensor / Switch "D" Circuit
DTC 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

DESCRIPTION

DTC Detection Condition:

A vehicle that is equipped with an Electronic Throttle Control System (ETCS) does not have a throttle cable. The APP sensor is mounted on the accelerator pedal bracket. The APP sensor has 2 sensor elements/signal outputs: VPA1 and VPA2. VPA1 is used to detect the actual accelerator pedal angle (used for engine control) and VPA2 is used to detect malfunctions in VPA1. Voltage applied to VPA1 and VPA2 changes between 0.2 V and 5 V in proportion to the accelerator pedal angle.

The ECM monitors the accelerator pedal angle from VPA1 and VPA2 signal outputs, and controls the throttle actuator based on these signals.






HINT: After confirming DTC P2120, P2122, P2123, P2125, P2127, P2128 and P2138, use the intelligent tester to confirm the APP sensor output voltage.

MONITOR DESCRIPTION

Monitor Strategy:

Typical Enabling Conditions:

Typical Malfunctions Thresholds:

Component Operating Range:

When either voltage output VPA1 or VPA2 deviates from the standard range, 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 APP sensor. The ECM illuminates the MIL and sets a DTC.

Example: When the voltage output of the VPA1 below 0.2 V or exceeds 4.8 V.

This monitor runs for 2 seconds (the first 2 seconds of engine idle) after the engine is started (1 trip detection logic).

FAIL-SAFE

The APP sensor has 2 (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 changes to limp mode. In limp mode, the remaining circuit is used to calculate the accelerator pedal opening angle 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 1-2:

Step 3-4:

Step 5:

INSPECTION PROCEDURE

HINT:
- Read freeze frame data using the intelligent tester. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
- This is the repair procedure for the Accelerator Pedal Position (APP) sensor.