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Key Switch (BCM Input) Circuit Check

WARNING: This page is about a different car, the 2011 Suzuki Equator. However, it is still accessible from the selected car via links, so may be relevant.

Regarding Wiring Diagram information, refer to POWER DOOR LOCK SYSTEM: WIRING DIAGRAM [KING CAB] or POWER DOOR LOCK SYSTEM: WIRING DIAGRAM [CREW CAB] .

DIAGNOSIS PROCEDURE

Step Action YES NO
1  CHECK KEY SWITCH INPUT SIGNAL 
With SDT
Check key switch "KEY ON SW" in "Data list" mode with SDT. Refer to [SDT FUNCTION (BCM - DOOR LOCK) ].
  • When key is inserted to ignition key cylinder:

    KEY ON SW: ON 

  • When key is removed from ignition key cylinder:

    KEY ON SW: OFF 


Without SDT
Check voltage between BCM connector M18 terminal 37 and ground.
Is the inspection result normal? 		 Key switch (insert) circuit is OK. GO TO 2
2  CHECK KEY SWITCH (INSERT) 
  1. Turn ignition switch OFF.
  2. Disconnect key switch connector.
  3. Check continuity between key switch terminals.

Is the inspection result normal? 		 Repair or replace harness or fuse. Replace key switch.
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