DTC P2123 Throttle/Pedal Position Sensor/Switch "D" Circuit High Input: Wiring Diagram

Fig 1: Identifying DTC P2123 Throttle/Pedal Position Sensor/Switch "D" High Input Wiring Diagram

Courtesy of SUBARU OF AMERICA, INC.

DIAGNOSTIC PROCEDURE FOR SYMPTOM

Step	Check	Yes	No
1 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR. Turn the ignition switch to OFF. Disconnect the connector from the ECM and accelerator pedal position sensor. Measure the resistance of harness between ECM and accelerator pedal position sensor connector. Connector & terminal (B135) No. 23 - (B315) No. 6: (B135) No. 29 - (B315) No. 5:	Is the resistance less than 1 Ω?	Go to step 2.	Repair the open circuit of the harness between the ECM and accelerator pedal position sensor connector.
2 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR. Connect the ECM. Measure the resistance between accelerator pedal position sensor connector and chassis ground. Connector & terminal (B315) No. 5 - Chassis ground:	Is the resistance less than 5 Ω?	Go to step 3.	Repair the harness and connector. NOTE: In this case, repair the following item: Open circuit of harness between ECM and engine ground Poor contact in ECM connector
3 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR. Turn the ignition switch to ON. Measure the voltage between accelerator pedal position sensor connector and chassis ground. Connector & terminal (B315) No. 6 (+) - Chassis ground (-):	Is the voltage 4.85 V or more?	Repair the short circuit to power source in the harness between the ECM and accelerator pedal position sensor connector.	Go to step 4.
4 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR. Turn the ignition switch to OFF. Disconnect the connectors from the ECM. Measure the resistance between ECM connectors. Connector & terminal (B135) No. 21 - (B135) No. 23:	Is the resistance 1 MΩ or more?	Repair the poor contact of accelerator pedal position sensor connector. Replace the accelerator pedal if defective. <Ref. to ACCELERATOR PEDAL .>	Repair the short circuit to power source in the harness between the ECM and accelerator pedal position sensor connector.