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DTC P081A: Starter Disable Circuit Low: Notes

-
DTC detecting condition:

Immediately at fault recognition

Trouble symptom:

Failure of engine to start

Wiring diagram:

Engine Electrical System Refer to WIRING SYSTEM>ENGINE ELECTRICAL SYSTEM .

Model without push button start

Courtesy of SUBARU OF AMERICA, INC.

Courtesy of SUBARU OF AMERICA, INC.
Model with push button start

G13626987

Courtesy of SUBARU OF AMERICA, INC.

G13626988

Courtesy of SUBARU OF AMERICA, INC.

CAUTION: Use the check board when measuring the ECM terminal voltage and resistance. Refer to ENGINE (DIAGNOSTICS) (H4DO)>GENERAL DESCRIPTION>PREPARATION TOOL>HOW TO USE CHECK BOARD .

NOTE: After the faulty parts are repaired or replaced, perform the final check in Basic Diagnostic Procedure. Refer to ENGINE (Diagnostics) (H4DO)>Basic Diagnostic Procedure>PROCEDURE .

CHECK HARNESS BETWEEN ECM AND M/B (STARTER CUT RELAY) (SHORT TO GROUND) .
1. Turn the ignition switch to OFF.
2. Disconnect the connector from ECM.
3. Remove the starter cut relay.
4. Measure the resistance between the ECM connector and engine ground.
  Connector & terminal
  
  (B62) No. 24 - Engine ground:
Is the resistance 1 MΩ or more?

Yes : Go to 2.

No : Repair the short circuit to ground in harness between ECM connector and M/B (starter cut relay).
CHECK HARNESS BETWEEN ECM AND M/B (STARTER CUT RELAY) (OPEN) .
Measure the resistance of harness between ECM connector and M/B (starter cut relay) terminal.

Connector & terminal

(B62) No. 24 - No. 4:

Is the resistance less than 1 Ω?

Yes : Go to 3.

No : Repair the open circuit of harness between ECM connector and M/B (starter cut relay) connector.
CHECK STARTER CUT RELAY .
Check the starter cut relay. Refer to STARTING/CHARGING SYSTEMS (H4DO)>STARTER RELAY .

Is the check result OK?

Yes : Repair the poor contact of ECM connector.

No : Replace the starter cut relay. Refer to STARTING/CHARGING SYSTEMS (H4DO)>Starter Relay>LOCATION .