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Home >> Subaru >> 2005 >> Outback XT Limited, Automatic >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 8 (Engine Controls - Engine (Diagnostics) (H4SO)) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> DTC P2122 Throttle/Pedal Position Sensor/Switch "D" Circuit Low Input
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DTC P2122 Throttle/Pedal Position Sensor/Switch "D" Circuit Low Input

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

DTC DETECTING CONDITION: 

TROUBLE SYMPTOM: 

WIRING DIAGRAM: 

Fig 1: DTC P2122 Throttle/Pedal Position Sensor/Switch "D" Circuit Low Input
G03828519Courtesy of SUBARU OF AMERICA, INC.
DTC P2122 THROTTLE/PEDAL POSITION SENSOR/SWITCH "D" CIRCUIT LOW INPUT DIAGNOSIS

Step Check Yes No
1. CHECK OUTPUT VOLTAGE OF ACCELERATOR POSITION SENSOR. 
  1. Turn the ignition switch to ON.
  2. Read the data of main accelerator position sensor signal using Subaru Select Monitor.
NOTE:
  • Subaru Select Monitor

For detailed operation procedure, refer to the "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 IN CONNECTORS. 

Check poor contact in connectors between ECM and accelerator position sensor.

Is there poor contact in connectors between ECM and accelerator position sensor? Repair the poor contact in connectors. Connector has returned to its normal condition at this time. A temporary poor contact of the connector may be the cause.
3. CHECK HARNESS BETWEEN ECM AND ACCELERATOR POSITION SENSOR. 
  1. Turn the ignition switch to OFF.
  2. Disconnect the connector from ECM.
  3. Disconnect the connector from accelerator position sensor.
  4. Measure the resistance between ECM connector and accelerator position sensor.

    Connector & terminal 

    (B136) No. 17 - (B315) No. 5: 

    (B136) No. 15 - (B315) No. 3: 

Is the resistance less than 1 Ω? Go to step 4.  Repair the open harness connector.
4. CHECK HARNESS BETWEEN ECM AND ACCELERATOR POSITION SENSOR. 

Measure the resistance between ECM connector and chassis ground.

Connector & terminal 

(B136) No. 17 - Chassis ground: 

(B136) No. 15 - Chassis ground: 

Is the resistance more than 1 MΩ? Go to step 5.  Repair the open harness connector.
5. CHECK ACCELERATOR POSITION SENSOR POWER SUPPLY 
  1. Connect the ECM connector.
  2. Turn the ignition switch to ON.
  3. Measure the voltage between accelerator position sensor connector and chassis ground.

    Connector & terminal 

    (B315) No. 3 (+) - Chassis ground (-): 

Is the voltage 4.5 - 5.5 V? Go to step 6.  Repair the poor contact in ECM connector. If problem persists, replace the ECM. < Ref. to ENGINE CONTROL MODULE (ECM) . >
6. CHECK ACCELERATOR POSITION SENSOR. 

Measure the resistance of accelerator position sensor.

Terminals No. 3 - No. 4: 

Is the resistance 1.2 - 4.8 kΩ? Go to step 7.  Replace the accelerator position sensor.
7. CHECK ACCELERATOR POSITION SENSOR. 

Measure the resistance of accelerator position sensor when accelerator pedal is released.

Terminals 

No. 5 - No. 4: 

Is the resistance 0.2 - 1.0 kΩ? Go to step 8.  Replace the accelerator position sensor.
8. CHECK ACCELERATOR POSITION SENSOR. 

Measure the resistance of accelerator position sensor when acceleration pedal is being depressed.

Terminals 

No. 5 - No. 4: 

Is the resistance 0.5 - 2.5 kΩ? Repair the poor contact in ECM connector. If problem persists, replace the ECM. < Ref. to ENGINE CONTROL MODULE (ECM) . > Replace the accelerator position sensor.