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DTC P2127 Throttle/Pedal Position Sensor / Switch "E" Circuit Low Input

DTC DETECTING CONDITION:

Immediately at fault recognition
GENERAL DESCRIPTION < Ref. to DTC P2127 THROTTLE/PEDAL POSITION SENSOR/SWITCH "E" CIRCUIT LOW INPUT , Diagnostic Trouble Code (DTC) Detecting Criteria. >

TROUBLE SYMPTOM:

Erroneous idling
Poor driving performance

WIRING DIAGRAM:

Fig 1: Throttle/Pedal Position Sensor / Switch "E" Circuit Low Input - Wiring Diagram

G05017619

DIAGNOSIS PROCEDURE

Step	Check	Yes	No
1 CHECK ACCELERATOR PEDAL POSITION SENSOR OUTPUT. Turn the ignition switch to ON. Read the data of sub accelerator pedal position sensor signal using Subaru Select Monitor. NOTE: Subaru Select Monitor For detailed operation procedure, refer to "READ CURRENT DATA FOR ENGINE". < Ref. to SUBARU SELECT MONITOR . >	Is the voltage more than 0.4 V?	Go to step 2.	Go to step 3 .
2 CHECK POOR CONTACT. Check poor contact of connector between ECM and accelerator pedal position sensor.	Is there poor contact?	Repair the poor contact.	Temporary poor contact occurred, but it is normal at present.
3 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR. Turn the ignition switch to OFF. Disconnect the connectors from ECM. Disconnect the connectors from accelerator pedal position sensor. Measure the resistance between ECM connector and accelerator pedal position sensor connector. Connector & terminal (B135) No. 31 - (B315) No. 2: (B135) No. 22 - (B315) No. 1:	Is the resistance less than 1 Ω?	Go to step 4.	Repair the open circuit of harness connector.
4 CHECK HARNESS BETWEEN ECM AND ACCELERATOR PEDAL POSITION SENSOR. Measure the resistance between ECM connector and chassis ground. Connector & terminal (B135) No. 31 - Chassis ground: (B135) No. 22 - Chassis ground:	Is the resistance more than 1 MΩ?	Go to step 5.	Repair the chassis short circuit of harness.
5 CHECK POWER SUPPLY OF 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. 1 (+) - Chassis ground (-):	Is the voltage 4.5 - 5.5 V?	Go to step 6.	Repair the poor contact of ECM connector. Replace the ECM If defective. < Ref. to ENGINE CONTROL MODULE (ECM) . >
6 CHECK ACCELERATOR PEDAL POSITION SENSOR. Measure the resistance of accelerator pedal position sensor. Terminals No. 1 - No. 2:	Is the resistance between 0.75 and 3.15 kΩ?	Go to step 7.	Replace the accelerator pedal position sensor.
7 CHECK ACCELERATOR PEDAL POSITION SENSOR. Measure the resistance of accelerator pedal position sensor. Terminals No. 3 - No. 5: Check the measured value is within the specification without depressing the accelerator pedal.	Is the resistance between 0.15 and 0.63 kΩ?	Go to step 8.	Replace the accelerator pedal position sensor.
8 CHECK ACCELERATOR PEDAL POSITION SENSOR. Measure the resistance of accelerator pedal position sensor. Terminals No. 3 - No. 5: Check the measured value is within the specification with the accelerator pedal depressed.	Is the resistance between 0.28 and 1.68 kΩ?	Repair the poor contact of ECM connector. Replace the ECM if defective. < Ref. to ENGINE CONTROL MODULE (ECM) . >	Replace the accelerator pedal position sensor.