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.
DTC P0512: Starter (Switch) Request Circuit: Notes
1. -
DTC detecting condition:
Detected when three consecutive driving cycles with fault occur.
Trouble symptom:
Auto Start Stop does not operate.
Wiring diagram:
Auto Start Stop Ref. to WIRING SYSTEM (CROSSTREK MODEL (EXCEPT FOR HEV))>AUTO START STOP .
- Use the check board when measuring the TCM terminal voltage and resistance.
- After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. Ref. to AUTO START STOP (DIAGNOSTICS)>BASIC DIAGNOSTIC PROCEDURE .
- CHECK DATA MONITOR
.
- Turn the ignition switch to ON. (Engine OFF)
- Read the data of [Starter Switch] using Subaru Select Monitor. Ref. to AUTO START STOP (DIAGNOSTICS)>DATA MONITOR .
Is [ON] displayed in [Starter Switch]?
Yes: Go to 2.
No: The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.
NOTE:In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
- CHECK INPUT VOLTAGE OF TCM
.
- Turn the ignition switch to OFF.
- Disconnect the TCM connector.
- Turn the ignition switch to ON.
- Measure the voltage between TCM and chassis ground.
Connector and terminal
(T10) No. 45 (+) - Chassis ground (-):
Is the voltage 10 V or more?
Yes: Check the following item and repair if necessary.
- Model with push button start
Repair the short circuit to power supply in harness between keyless access control module and TCM connector.
- Model without push button start
Short circuit to power supply in harness between ignition switch and TCM connector
Sticking inside the ignition switch
No: Check for poor contact of TCM connector. Replace the TCM if no fault is found. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR580 CROSSTREK)>TRANSMISSION CONTROL MODULE (TCM) .
NO RELATED
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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.