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DTC P1F00: Self-Shut Off Relay Circuit Low: Notes

  1. -

DTC detecting condition: 

Immediately at fault recognition

Trouble symptom: 

Driveability getting worse.

Wiring diagram: 

AWD control system Ref. to WIRING SYSTEM (CROSSTREK MODEL (HEV))>AWD CONTROL SYSTEM .

G13237849Courtesy of SUBARU OF AMERICA, INC.
G13617896Courtesy of SUBARU OF AMERICA, INC.
  1. CHECK HARNESS  .
    1. Disconnect the AWD Control Module connector.
    2. Remove the AWD Control Module relay.
    3. Measure the resistance between AWD Control Module connector and relay holder.

    Connector & terminal 

    (B648) No. 18 - (B225) No. 36:

    (B648) No. 2 - (B225) No. 38:

    (B648) No. 15 - (B225) No. 38:

    Is the resistance less than 1 Ω?

    Yes:  Go to  2.

    No:  Repair the open circuit of harness.

  2. CHECK HARNESS  .

    Measure the resistance between AWD Control Module connector and chassis ground.

    Connector & terminal 

    (B648) No. 18 - Chassis ground:

    (B648) No. 2 - Chassis ground:

    (B648) No. 15 - Chassis ground:

    Is the resistance 1 MΩ or more?

    Yes:  Go to  3.

    No:  Repair the short circuit of harness.

  3. CHECK RELAY POWER SUPPLY  .

    Measure the voltage between relay holder and chassis ground.

    Connector & terminal 

    (B225) No. 35 (+) - Chassis ground (-):

    (B225) No. 37 (+) - Chassis ground (-):

    Is the voltage 10 V or more?

    Yes:  Go to  4.

    No:  Repair the open or short circuit of harness.

  4. CHECK AWD CONTROL MODULE RELAY  .

    Measure the resistance between the AWD Control Module relay terminals.

    Connector & terminal 

    No. 35 - No. 36:

    Is the resistance 70 - 180 Ω?

    Yes:  Go to  5.

    No:  Replace AWD Control Module relay.

  5. CHECK AWD CONTROL MODULE RELAY  .

    Measure the resistance between the AWD Control Module relay terminals.

    Connector & terminal 

    No. 37 - No. 38:

    Is the resistance 1 MΩ or more?

    Yes:  Go to  6.

    No:  Replace AWD Control Module relay.

  6. REPLACE AWD CONTROL MODULE RELAY  .
    1. Replace AWD Control Module relay.
    2. Connect the AWD Control Module connector.
    3. Using the Subaru Select Monitor, read data of [Main Power Supply Voltage] in the [Data Monitor] of [AWD Control]. Ref. to AWD CONTROL (DIAGNOSTICS)>DATA MONITOR .

    Is [Main Power Supply Voltage] 10 [V] or more?

    Yes:  Check for poor contact of AWD Control Module connector. Replace the AWD Control Module if no fault is found. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TH2A)>AWD CONTROL MODULE .

    No:  AWD Control Module relay is defective.