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Detailed Flow

NOTE: To ensure a complete and thorough diagnosis, the battery, starter and alternator test segments must be done as a set from start to finish.
  1. PRELIMINARY INSPECTION 

    Perform the preliminary inspection. Refer to "INSPECTION PROCEDURE ".

    : GO TO 2.

  2. STOP POWER GENERATION VOLTAGE VARIABLE CONTROL SYSTEM 

    Stop the operation of the power generation voltage variable control in either of the following procedures.

    • After selecting "ENGINE" of "SELECT SYSTEM" using CONSULT, set the DUTY value of "ALTERNATOR DUTY" to 0 % by selecting "ALTERNATOR DUTY" of "Active Test". Continue "Active Test" until the end of inspection. (When the DUTY value is 0 or 100 %, the normal power generation is performed according to the characteristic of the IC voltage regulator of the alternator.)
    • Turn the ignition switch OFF, and disconnect the battery current sensor connector. [However, DTC (P1550 - P1554) of the engine might remain. After finishing the inspection, connect the battery current sensor connector and erase the self-diagnosis results history of the engine using CONSULT.]

      : GO TO 3.

  3. DIAGNOSIS WITH STARTING/CHARGING SYSTEM TESTER 

    Perform the charging system test using Starting/Charging System Tester (SST: J-44373). For details and operating instructions, refer to Technical Service Bulletin.

    Test result 

    CHARGING SYSTEM NORMAL: Charging system is normal and will also show "DIODE RIPPLE" test result.

    NO CHARGING VOLTAGE: GO TO 4.

    LOW CHARGING VOLTAGE: GO TO  12.

    HIGH CHARGING VOLTAGE: GO TO  14.

    DIODE RIPPLE NORMAL: Diode ripple is OK and will also show "CHARGING VOLTAGE" test result.

    EXCESS RIPPLE DETECTED: Replace the alternator. Perform "DIODE RIPPLE" test again using Starting/Charging System Tester (SST: J-44373) to confirm repair.

    DIODE RIPPLE NOT DETECTED: GO TO 4.

  4. INSPECTION WITH CHARGE WARNING LAMP (IGNITION SWITCH IS ON) 

    Turn the ignition switch ON.

    Does the charge warning lamp illuminate? 

    YES: GO TO  6.

    NO: GO TO 5.

  5. "L" TERMINAL CIRCUIT (OPEN) INSPECTION 

    Check "L" terminal circuit (open). Refer to "DIAGNOSIS PROCEDURE ".

    Is the "L" terminal circuit normal? 

    YES: Replace alternator.

    NO: Repair as needed.

  6. INSPECTION WITH CHARGE WARNING LAMP (IDLING) 

    Start the engine and run it at idle.

    Does the charge warning lamp turn OFF? 

    YES: GO TO  9.

    NO: GO TO 7.

  7. "L" TERMINAL CIRCUIT (SHORT) INSPECTION 

    Check "L" terminal circuit (short). Refer to "DIAGNOSIS PROCEDURE ".

    Is the "L" terminal circuit normal? 

    YES: GO TO 8.

    NO: Repair as needed.

  8. "S" TERMINAL CIRCUIT INSPECTION 

    Check "S" terminal circuit. Refer to "DIAGNOSIS PROCEDURE ".

    Is the "S" terminal circuit normal? 

    YES: GO TO  10.

    NO: Repair as needed.

  9. INSPECTION WITH CHARGE WARNING LAMP (ENGINE AT 3, 000 RPM) 

    Increase and maintain the engine speed at 3, 000 rpm.

    Does the charge warning lamp remain off? 

    YES: GO TO  11.

    NO: GO TO 10.

  10. INSPECTION OF ALTERNATOR PULLEY 

    Check alternator pulley. Refer to "VQ37VHR: INSPECTION " (VQ37VHR) or "VK56VD: INSPECTION " (VK56VD).

    Is alternator pulley normal? 

    YES: Replace alternator.

    NO: Repair as needed.

  11. "B" TERMINAL CIRCUIT INSPECTION 

    Check "B" terminal circuit. Refer to "DIAGNOSIS PROCEDURE ".

    Is "B" terminal circuit normal? 

    YES: Replace alternator.

    NO: Repair as needed.

  12. "B" TERMINAL CIRCUIT INSPECTION 

    Check "B" terminal circuit. Refer to "DIAGNOSIS PROCEDURE ".

    Is "B" terminal circuit normal? 

    YES: GO TO 13.

    NO: Repair as needed.

  13. INSPECTION OF ALTERNATOR PULLEY 

    Check alternator pulley. Refer to "VQ37VHR: INSPECTION " (VQ37VHR) or "VK56VD: INSPECTION " (VK56VD).

    Is alternator pulley normal? 

    YES: Replace alternator.

    NO: Repair as needed.

  14. "S" TERMINAL CIRCUIT INSPECTION 

    Check "S" terminal circuit. Refer to "DIAGNOSIS PROCEDURE ".

    Is the "S" terminal circuit normal? 

    YES: Replace alternator.

    NO: Repair as needed.