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Home >> Subaru >> 2007 >> Forester XT Limited, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls (Diagnostics) (H4DOTC) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> DTC P2127 Throttle/Pedal Position Sensor/Switch "E" Circuit Low Input >> Wiring Diagram
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DTC P2127 Throttle/Pedal Position Sensor/Switch "E" Circuit Low Input: Wiring Diagram

Fig 1: Throttle/Pedal Position Sensor/Switch E Circuit Low Input - Wiring Diagram
G05326352Courtesy of SUBARU OF AMERICA, INC.
DIAGNOSIS PROCEDURE CHART

Step Check Yes No
1 CHECK ACCELERATOR PEDAL POSITION SENSOR OUTPUT. 
  1. Turn the ignition switch to ON.
  2. Read the data of sub accelerator pedal position sensor signal using Subaru Select Monitor. <Ref. to SUBARU SELECT MONITOR . >
 Is the voltage 0.4 V or more? 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. 
  1. Turn the ignition switch to OFF.
  2. Disconnect the connectors from ECM.
  3. Disconnect the connectors from accelerator pedal position sensor.
  4. Measure the resistance between ECM connector and accelerator pedal position sensor connector.

    Connector & terminal 

    (B135) No. 22 - (B315) No. 1: 

    (B135) No. 31 - (B315) No. 3: 

 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. 22 - Chassis ground: 
(B135) No. 31 - Chassis ground: 		 Is the resistance 1 MΩ or more? Go to step 5.  Repair the chassis short circuit of harness.
5 CHECK HARNESS BETWEEN ECM CONNECTOR AND ACCELERATOR PEDAL POSITION SENSOR. 
  1. Connect the ECM connector.
  2. Measure the resistance between accelerator pedal position sensor connector and chassis ground.

    Connector & terminal 

    (B315) No. 2 - Chassis ground: 

 Is the resistance less than 5 Ω? Go to step 6.  Repair poor contact in ECM connector. Replace the ECM if defective. <Ref. to ENGINE CONTROL MODULE (ECM) . >
6 CHECK POWER SUPPLY OF ACCELERATOR PEDAL POSITION SENSOR. 
  1. Turn the ignition switch to ON.
  2. 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? Replace the accelerator pedal position sensor. <Ref. ACCELERATOR PEDAL Accelerator Pedal. > Repair poor contact in ECM connector. Replace the ECM if defective. <Ref. to ENGINE CONTROL MODULE (ECM) . >
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