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Home >> Infiniti >> 2008 >> G35 Base >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System - DTCS P0441 Through P0643 >> DTC P0603: ECM Power Supply >> Diagnosis Procedure
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Diagnosis Procedure

  1. CHECK ECM POWER SUPPLY
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check the voltage between ECM harness connector and ground.
      TERMINALS VOLTAGE REFERENCE

      ECM Ground Voltage
      Connector Terminal
      F102 93 Ground Battery voltage

    Is the inspection result normal? 

    YES: GO TO  3.

    NO: GO TO 2.

  2. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E3, F1
    • 15A fuse (No. 50)
    • IPDM E/R harness connector E7
    • Harness for open or short between ECM and battery

      Repair or replace harness or connectors.

  3. CHECK INTERMITTENT INCIDENT

    Refer to "INTERMITTENT INCIDENT ".

    Is the inspection result normal? 

    YES: GO TO 4.

    NO: Repair or replace harness or connectors.

  4. PERFORM DTC CONFIRMATION PROCEDURE

    With CONSULT-III 

    1. Turn ignition switch ON.
    2. Select "SELF-DIAG RESULTS" mode with CONSULT-III.
    3. Touch "ERASE".
    4. Perform DTC Confirmation Procedure.

      See "DTC LOGIC ".

    With GST 

    1. Turn ignition switch ON.
    2. Select Service $04 with GST.
    3. Perform DTC Confirmation Procedure.

      See "DTC LOGIC ".

    Is the 1st trip DTC P0603 displayed again? 

    YES: GO TO 5.

    NO: INSPECTION END

  5. REPLACE ECM
    1. Replace ECM.
    2. Go to "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT : SPECIAL REPAIR REQUIREMENT ".

      INSPECTION END

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