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BCM General Description

The BCM incorporates relays and controllers which are used for the following systems and controls them.

BCM Input/Output Table 

BCM INPUT/OUTPUT REFERENCE CHART

Control Input Output
Power door lock system
  • Key cylinder switch
  • Manual door lock switch
  • Each door lock actuator
Keyless entry system
  • Key reminder switch
  • Keyless entry receiver
  • Each door switch
  • Each door lock actuator
  • Turn signal and hazard warning relay
  • Interior light
Keyless start system(1) (Door lock function)
  • Keyless start control module
  • Each door lock actuator
  • Turn signal and hazard warning relay
  • Interior light
Keyless start system(1) (Trunk lid opener function)
  • Keyless start control module
  • Trunk lid opener actuator
Rear wiper(1)
  • Rear wiper switch (INT, LO, WASH(1)
  • Rear wiper relay
Combination meter
  • Tail light switch
  • Oil pressure switch
  • Parking brake switch
  • Driver side seat belt switch
  • Brake fluid level switch
  • Generator
  • Each door switch
  • TPMS receiver(1)
  • Combination meter
Interior light
  • Each door switch
  • Key reminder switch
  • Interior light
Warning buzzer
  • Key reminder switch
  • Tail light switch
  • Driver side door switch
  • Keyless start control module(1)
  • Warning buzzer (located in combination meter)
Rear end door window/back window defogger
  • Rear end door window/back window defogger switch
  • Generator
  • Rear end door window/back window defogger relay
Rear end door opener(1)
  • Manual door lock switch (unlock signal)
  • Key cylinder switch (unlock signal)
  • Keyless entry transmitter (unlock signal)
  • Rear end door opener switch
  • Rear end door opener relay
Door lock canceller
  • SDM (air bag deployment signal)
  • Each door lock actuator
Theft deterrent light
  • Ignition switch
  • Theft deterrent light (located in hazard warning switch)
Panic alarm function
  • Panic alarm request signal
  • Headlight low or high relay
  • Tail light relay
  • Horn relay
Tail light
  • Lighting switch
  • Tail light relay
Seat belt reminder(1)
  • Seat belt switch signal
  • Vehicle speed signal
  • Combination meter
  • Hazard warning switch
  • Warning buzzer (located in combination meter)
DRL system(1)
  • Lighting switch
  • ECM (engine ON, OFF signal)
  • Generator
  • Parking brake switch
  • Combination meter
  • Headlight low beam
Front fog light(1)
  • Lighting switch
  • Front fog light switch
  • Front fog light relay
Security alarm system(1)
  • Battery voltage
  • Door switch status
  • Door lock status
  • Ignition switch
  • Key reminder switch
  • Keyless start control module(1)
  • Horn relay
  • Hazard warning relay
  • Warning buzzer (located in combination meter)
  • Theft deterrent light (in hazard warning switch)
(1) If equipped Also, the BCM has a function to cause the interior light and open door warning light in the combination meter to turn off when any door is left open for longer than 15 minutes to reduce wasteful battery consumption. In addition, it is possible to check operation of actuator which is controlled by BCM by using the output test function of SUZUKI scan tool to operate actuator simulatively.