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Detailed Flow

WARNING: This page is about a different car, the 2013 Infiniti M56 and 2013 Infiniti M37. However, it is still accessible from the selected car via links, so may be relevant.
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 EXP-800 NI OR GR8-1200 NI 

    Perform the charging system test using Multitasking battery and electrical diagnostic station GR8-1200 NI or Battery and electrical diagnostic analyzer EXP-800 NI. Refer to the applicable Instruction Manual for proper testing procedures.

    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 Multitasking battery and electrical diagnostic station GR8-1200 NI or Battery and electrical diagnostic analyzer EXP-800 NI 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. Refer to "VQ37VHR: REMOVAL AND INSTALLATION (2WD) " (VQ37VHR [2WD]), "VQ37VHR: REMOVAL AND INSTALLATION (AWD) " (VQ37VHR [AWD]) or "VK56VD: REMOVAL AND INSTALLATION " (VK56VD).

    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 (WITH EXP-800 NI OR GR8-1200 NI) " (VQ37VHR) or "VK56VD: INSPECTION (WITH EXP-800 NI OR GR8-1200 NI) " (VK56VD).

    Is alternator pulley normal? 

    YES: Replace alternator. Refer to "VQ37VHR: REMOVAL AND INSTALLATION (2WD) " (VQ37VHR [2WD]), "VQ37VHR: REMOVAL AND INSTALLATION (AWD) " (VQ37VHR [AWD]) or "VK56VD: REMOVAL AND INSTALLATION " (VK56VD).

    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. Refer to "VQ37VHR: REMOVAL AND INSTALLATION (2WD) " (VQ37VHR [2WD]), "VQ37VHR: REMOVAL AND INSTALLATION (AWD) " (VQ37VHR [AWD]) or "VK56VD: REMOVAL AND INSTALLATION " (VK56VD).

    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 (WITH EXP-800 NI OR GR8-1200 NI) " (VQ37VHR) or "VK56VD: INSPECTION (WITH EXP-800 NI OR GR8-1200 NI) " (VK56VD).

    Is alternator pulley normal? 

    YES: Replace alternator. Refer to "VQ37VHR: REMOVAL AND INSTALLATION (2WD) " (VQ37VHR [2WD]), "VQ37VHR: REMOVAL AND INSTALLATION (AWD) " (VQ37VHR [AWD]) or "VK56VD: REMOVAL AND INSTALLATION " (VK56VD).

    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. Refer to "VQ37VHR: REMOVAL AND INSTALLATION (2WD) " (VQ37VHR [2WD]), "VQ37VHR: REMOVAL AND INSTALLATION (AWD) " (VQ37VHR [AWD]) or "VK56VD: REMOVAL AND INSTALLATION " (VK56VD).

    NO: Repair as needed.

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