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 Refer to WIRING SYSTEM (CROSSTREK MODEL (HEV))>AWD CONTROL SYSTEM .

Courtesy 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. Read the data of [Main Power Supply Voltage] using Subaru Select Monitor. Refer 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. Refer to CONTINUOUSLY VARIABLE TRANSMISSION (TH2A)>AWD CONTROL MODULE .

   No:  AWD control module relay is defective.