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Home >> Suzuki >> 2009 >> Equator RMZ-4 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (VQ40DE) - (3 Of 5) >> DTC P1421: Cold Start Control >> Diagnosis Procedure
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Diagnosis Procedure

DIAGNOSIS PROCEDURE

Step Action YES NO
PERFORM IDLE AIR VOLUME LEARNING 
Perform "Idle Air Volume Learning" in [PROCEDURE AFTER REPLACING ECM ].
Is Idle Air Volume Learning carried out successfully? 
Yes or No 
GO TO 2. Follow the instruction of Idle Air Volume Learning.
CHECK Intake system 
Check for the cause of intake air volume lacking. Refer to the following.
  • Crushed intake air passage
  • Intake air passage clogging

OK or NG 
GO TO 3. Repair or replace malfunctioning part
CHECK FUEL INJECTION SYSTEM FUNCTION 
Perform [P0171, P0174 FUEL INJECTION SYSTEM FUNCTION ] in DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION.
OK or NG 
GO TO 4. Go to [P0171, P0174 FUEL INJECTION SYSTEM FUNCTION ].
PERFORM DTC CONFIRMATION PROCEDURE 
  1. With SDT 
    1. Turn ignition switch ON.
    2. Select "DTC check" mode with SDT.
    3. Touch "Clear".
    4. Perform DTC Confirmation Procedure.  See [P1421 COLD START CONTROL ].
    5. Is the 1st trip DTC P1421 displayed again?
  2. With GST 
    1. Turn ignition switch ON.
    2. Select Service $04 with GST.
    3. Perform DTC Confirmation Procedure.  See [P1421 COLD START CONTROL ].
    4. Is the 1st trip DTC P1421 displayed again?

Yes or No 
GO TO 5. INSPECTION END 
REPLACE ECM 
  1. Replace ECM.
  2. Perform initialization of immobilizer system and registration of all immobilizer system ignition key IDs. Refer to [ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT: SPECIAL REPAIR REQUIREMENT ]
  3. Perform "VIN Registration" in [PROCEDURE AFTER REPLACING ECM ].
  4. Perform "Accelerator Pedal Released Position Learning" in [PROCEDURE AFTER REPLACING ECM ].
  5. Perform "Throttle Valve Closed Position Learning" in [PROCEDURE AFTER REPLACING ECM ].
  6. Perform "Idle Air Volume Learning" in [PROCEDURE AFTER REPLACING ECM ].
INSPECTION END