P1120

DTC P1120 ACCELERATOR PEDAL POSITION SENSOR CIRCUIT MALFUNCTION

CIRCUIT DESCRIPTION

DTC Detecting Condition:

Accelerator pedal position sensor is mounted on the accelerator pedal bracket and it has 2 sensors to detects the accelerator position and a malfunction of the accelerator position's own.

The accelerator pedal position sensor is the voltage applied to the terminals VPA and VPA2 of the ECM changes between 0 V and 5 V in proportion to the opening angle of the accelerator pedal.

The ECM judges the current opening angle of the accelerator pedal from these signals input from terminals VPA and VPA2 and the ECM controls the throttle motor based on these signals.

If this DTC is stored, the ECM shuts down the power for the throttle motor, and the throttle valve is fully closed by the return spring.

After confirming DTC P1120, use the OBD II scan tool or LEXUS hand-held tester to confirm the throttle valve opening percentage.

Wiring Diagram:

INSPECTION PROCEDURE

HINT: Read freeze frame data using LEXUS hand-held OBD II scan tool, or as freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting it is useful for determining whether the vehicle was running or stopped, the engine warmed up or not, the air-fuel ratio lean or rich, etc. at the time of the malfunction.

Step 1:

Step 2 - 4:

LEXUS Hand-held Tester

Step 1 - 3:

OBD II scan tool (excluding LEXUS hand-held tester):