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Home >> Infiniti >> 2012 >> EX35 Base, AWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Drivers Assistance Systems - ADAS >> Driver Assistance System (DCA) >> DTC/Circuit Diagnosis >> DTC C1A40: System Switch Circuit >> DTC Logic >> DTC Detection Logic
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DTC Detection Logic

DTC (On board display) Trouble diagnosis name DTC detection condition Possible causes
C1A40 (40) SYSTEM SW CIRC If the IBA OFF switch is stuck to ON
  • IBA OFF switch circuit
  • IBA OFF switch
  • Brake booster control unit
NOTE: If DTC "C1A40" is displayed along with DTC "U1000", first diagnose the DTC "U1000". Refer to "ICC SENSOR INTEGRATED UNIT: DTC LOGIC ".