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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 >> On Board Diagnosis Logic
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On Board Diagnosis Logic

NOTE: If DTC P1421 is displayed with other DTC, first perform the trouble diagnosis for other DTC.
DTC DETECTING CONDITION AND POSSIBLE CAUSE

DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1421
1421
Cold start emission reduction strategy monitoring ECM does not control ignition timing and engine idle speed properly when engine is started with prewarming up condition.
  • Lack of intake air volume
  • Fuel injection system
  • ECM