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DTC P1A25: Dc/Dc Converter 1 Circuit 1 Temperature: Notes

DTC detecting condition: 

Detected when two consecutive driving cycles with fault occur.

Trouble symptom: 

CAUTION: After servicing or replacing faulty parts, perform the last step of the basic diagnostic procedure. Ref. to AUTO START STOP (DIAGNOSTICS)>BASIC DIAGNOSTIC PROCEDURE .
  1. CHECK REPEATABILITY  .
    1. Using the Subaru Select Monitor, perform the clear memory. Ref. to COMMON (DIAGNOSTICS)>CLEAR MEMORY .
    2. Using the Subaru Select Monitor, perform [Engine stop control] in the active test to stop the engine. Ref. to AUTO START STOP (DIAGNOSTICS)>ACTIVE TEST .
      CAUTION: Do not release the brake pedal to prevent sudden acceleration of the vehicle.
    3. Operate the Auto Start Stop cancel switch to restart the engine.
    4. Turn the ignition switch to OFF and wait for 10 seconds.
    5. Using the Subaru Select Monitor, read the DTC after repeating the procedure from step  2 to  4 two times. Ref. to AUTO START STOP (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

    Is DTC other than P1A25 and P1A26 displayed?

    Yes:  Perform the diagnosis according to the DTC. Ref. to AUTO START STOP (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)>LIST .

    No:  Go to  2.

  2. CHECK DTC  .

    Read the DTC using Subaru Select Monitor. Ref. to AUTO START STOP (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

    Is DTC P1A25 or P1A26 displayed?

    Yes:  Check for the poor contact of DC/DC converter 1 connector. Replace the DC/DC converter 1 if no fault is found. Ref. to STARTING/CHARGING SYSTEMS (H4DO)>AUTO START STOP DC/DC CONVERTER .

    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.