DTC P0512: Starter (Switch) Request Circuit: Notes

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>AUTO START STOP .

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK DATA MONITOR  .
   1. Turn the ignition switch to ON. (Engine OFF)
   2. 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  .
2. CHECK INPUT VOLTAGE OF TCM  .
   1. Turn the ignition switch to OFF.
   2. Disconnect the TCM connector.
   3. Turn the ignition switch to ON.
   4. Measure the voltage between TCM and chassis ground.

      Connector & 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)>TRANSMISSION CONTROL MODULE (TCM) .