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Home >> Infiniti >> 2011 >> M37 Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTCS P1233 To P2A03 >> DTC P1421: Cold Start Control >> DTC Logic >> DTC Confirmation Procedure
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DTC Confirmation Procedure

  1. PRECONDITIONING

    If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.

    1. Turn ignition switch OFF and wait at least 10 seconds.
    2. Turn ignition switch ON.
    3. Turn ignition switch OFF and wait at least 10 seconds.

      TESTING CONDITION: 

      Before performing the following procedure, confirm that battery voltage is more than 11 V at idle. 

      GO TO 2.

  2. PERFORM DTC CONFIRMATION PROCEDURE
    1. Turn ignition switch OFF and wait at least 10 seconds.
    2. Turn ignition switch ON.
    3. Select "DATA MONITOR" mode with CONSULT-III.
    4. Check the indication of "COOLAN TEMP/S".

      If it is between 7°C (45°F) and 36°C (97°F), go to the following steps.

      If it is below 7°C (45°F), warm engine up to more than 7°C (45°F) and retry from step  1.

      If it is above 36°C (97°F), cool engine down to less than 36°C (97°F) and retry from step  1.

    5. Start engine and let it idle for 5 minutes.
    6. Check 1st trip DTC.

      Is 1st trip DTC detected? 

      YES: Go to "DIAGNOSIS PROCEDURE ".

      NO: INSPECTION END