Mike's Workshop Manuals: Service manuals for every vehicle
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

Diagnosis Procedure

DIAGNOSIS PROCEDURE

Step Action YES NO
1  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.
2  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
3  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 ].
4  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 
5  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