2021 Subaru Ascent BaseFACTORY OEM SERVICE PROCEDURE

Charging System: Inspection

Inspection when charge warning light illuminates

NOTE: If the alternator overheats, the charge warning light illuminates temporarily.
  1. CHECK DTC  .

    Read the DTC using Subaru Select Monitor.

    Is DTC detected?

    Yes 

    1. Repair the corresponding system.
    2. Go to  2.

    No 

    Go to  2.

  2. CHECK V-BELT  .

    Check the V-belt for abnormalities. Ref. to MECHANICAL (H4DOTC)>V-belt>INSPECTION .

    Is the V-belt normal?

    Yes 

    Go to  3.

    No 

    Replace the V-belt or V-belt tensioner assembly. Ref. to MECHANICAL (H4DOTC)>V-BELT .

  3. CHECK VOLTAGE OF GENERATOR B TERMINAL  .

    Check the voltage of the generator terminal B.

    Is the battery voltage applied?

    Yes 

    Go to  4.

    No 

    Repair the harness between generator and MAIN SBF.

  4. CHECK CONTINUITY BETWEEN GENERATOR MAIN BODY AND CHASSIS GROUND  .

    Check continuity between generator main body and chassis ground.

    Is there continuity?

    Yes 

    Go to  5.

    No 

    Check and repair the installation condition of the generator, chassis ground and engine ground.

  5. CHECK COMBINATION METER  .

    Perform the self-diagnosis of combination meter. Ref. to INSTRUMENTATION/DRIVER INFO>Combination Meter System>OPERATION>SELF-DIAGNOSIS DISPLAY MODE .

    Is the charge warning light OK?

    Yes 

    Repair or replace the generator. Ref. to STARTING/CHARGING SYSTEMS (H4DOTC)>GENERATOR .

    No 

    Replace the combination meter. Ref. to INSTRUMENTATION/DRIVER INFO>COMBINATION METER .

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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.