Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
07 Starter Circuit Failure
Detecting condition:
When judging that the engine does not start running when the engine is restarted.
Trouble symptom:
After the engine stops, a buzzer sounds and the Auto Start Stop is canceled.
Wiring diagram:
- ENGINE TYPE FB
Auto Start Stop Refer to WIRING SYSTEM>AUTO START STOP>WIRING DIAGRAM>ENGINE TYPE FB .
- ENGINE TYPE FA
Auto Start Stop Refer to WIRING SYSTEM>AUTO START STOP>WIRING DIAGRAM>ENGINE TYPE FA .
- CHECK ENGINE START FAILURE
.
Start the engine using the ignition key or push button ignition switch.
Does the engine start?
Yes : Go to 2.
No : Inspect according to the general diagnosis table. Refer to ENGINE (DIAGNOSTICS) (H4DO)>DIAGNOSTICS WITH PHENOMENON . Refer to ENGINE (DIAGNOSTICS) (H4DOTC)>DIAGNOSTICS WITH PHENOMENON .
- CHECK Auto Start Stop STATUS
.
- Using the Subaru Select Monitor, perform [Engine stop control] in the active test to stop the engine. Refer to AUTO START STOP (DIAGNOSTICS)>Active Test .
- Operate the Auto Start Stop cancel switch to restart the engine.
Does the starter motor operate?
Yes : Go to 4.
No : Go to 3.
- CHECK Auto Start Stop STATUS
.
- Using the Subaru Select Monitor, perform [Engine stop control] in the active test to stop the engine. Refer to AUTO START STOP (DIAGNOSTICS)>Active Test .
- Read the data of [ECM Restart Request Signal State] using Subaru Select Monitor. Refer to AUTO START STOP (DIAGNOSTICS)>Data Monitor .
- Operate the Auto Start Stop cancel switch to restart the engine.
Did the display of [ECM Restart Request Signal State] change to [ON] at restarting?
Yes : Go to 4.
No : Check the harness between TCM connector and ECM connector.
ENGINE TYPE FB
(T21) No. 23 - (E53) No. 36
ENGINE TYPE FA
(B67) No. 23 - (E51) No. 19
- CHECK DTC
.
Read the DTC of [Engine] using the Subaru Select Monitor. Refer to ENGINE (DIAGNOSTICS) (H4DO)>DIAGNOSTIC TROUBLE CODE (DTC) . Refer to ENGINE (DIAGNOSTICS) (H4DOTC)>DIAGNOSTIC TROUBLE CODE (DTC) .
Are any DTCs displayed?
Yes : Perform the diagnosis according to the DTC. Refer to ENGINE (DIAGNOSTICS) (H4DO)>Diagnostic Trouble Code (DTC)>LIST . Refer to ENGINE (DIAGNOSTICS) (H4DOTC)>Diagnostic Trouble Code (DTC)>LIST .
No : Inspect according to the general diagnosis table. Refer to ENGINE (DIAGNOSTICS) (H4DO)>DIAGNOSTICS WITH PHENOMENON . Refer to ENGINE (DIAGNOSTICS) (H4DOTC)>DIAGNOSTICS WITH PHENOMENON .
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.