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

WARNING: This page is about a different variant/trim than selected.

DTC DETECTING CONDITION:

Immediately at fault recognition
GENERAL DESCRIPTION < Ref. to DTC P2123 THROTTLE/PEDAL POSITION SENSOR/SWITCH "D" CIRCUIT HIGH INPUT , Diagnostic Trouble Code (DTC) Detecting Criteria. >

TROUBLE SYMPTOM:

Erroneous idling
Poor driving performance

CAUTION: After repair or replacement of faulty parts, conduct Clear Memory Mode < Ref. to , OPERATION , Clear Memory Mode. > and Inspection Mode < Ref. to , PROCEDURE , Inspection Mode. >.

WIRING DIAGRAM:

Fig 1: DTC P2123 Throttle/Pedal Position - Wiring Diagram And Connector Terminal

Courtesy of SUBARU OF AMERICA, INC.

DIAGNOSTIC PROCEDURE DTC P2123

Step	Check	Yes	No
1 CHECK OUTPUT VOLTAGE OF ACCELERATOR PEDAL POSITION SENSOR. Turn the ignition switch to ON. Read the data of main accelerator pedal position sensor signals, using Subaru Select Monitor.	Is the voltage less than 4.8 V?	Go to step 2 .	Go to step 3 .
2 CHECK POOR CONTACT IN CONNECTORS Check poor contact in connectors between ECM and accelerator pedal position sensor.	Is there any poor contact in connectors between ECM and accelerator pedal position sensor?	Repair the poor contact in connectors.	Connector has returned to its normal condition at this time. A temporary poor contact in the connector might have been the cause.
3 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Disconnect the connector from accelerator pedal position sensor. Measure the resistance between ECM connector and accelerator pedal position sensor. Connector & terminal (B136) No. 34 - (B315) No. 4:	Is the resistance less than 1 Ω?	Go to step 4 .	Repair the open harness connector.
4 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR. Connect the ECM connector. Measure the resistance between accelerator pedal position sensor and chassis ground. Connector & terminal (B315) No. 4 - Chassis ground:	Is the resistance less than 5 Ω?	Go to step 5 .	Repair the poor contact in ECM connector. If problem persists, replace the ECM. < Ref. to ENGINE CONTROL MODULE (ECM) . >
5 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR. Connect the ECM connector. Turn the ignition switch to ON. Measure the voltage between accelerator pedal position sensor connector and chassis ground. Connector & terminal (B315) No. 5 (+) - Chassis ground (-):	Is the voltage less than 6 V?	Go to step 6 .	Repair the battery short of harness between ECM connector and accelerator pedal position sensor.
6 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance between ECM connectors. Connector & terminal (B136) No. 28 (+) - (B136) No. 15: (B136) No. 28 (+) - (B136) No. 16:	Is the resistance more than 1 MΩ?	Repair the poor contact in electronic throttle control connector. If problem persists, replace the accelerator pedal position sensor.	Repair the short to sensor power supply.