1.
Description : It cuts automatically power to be provided with load for reducing useless dark current according to vehicle state.
General function : Interior Junction Box + some functions of BCM
It controls loads with CAN communication and IPS.
Main function
Low speed CAN communication(100 kbps)
Self diagnostics(Lamp open/short)
Fail safe(When MCU/CAN is fail, Head lamp / Tail lamp directly drive)
Protection of bulb over-voltage(PWM function)
Cut of Over-load and Short : PCL(Program Current Limit)
Description : It cuts automatically power to be provided with load for reducing useless dark current according to vehicle state.
SJB had 3 modes, "Normal Mode", "Sleep Mode", "Power Off Mode". Auto cut of dark current practice in "Sleep Mode".
"Sleep" condition : IG OFF, constant input switch, CAN network doesn't activate.
"Sleep" resolutive condition : Any switch inputs, CAN network activates, KEY ON, IGN ON
"Power OFF" condition : The setting time of timer which is used by cutting a load power expires.
"Normal Mode" : SJB function normally activates.
"Sleep Mode" : It is low power mode and activates for reducing electricity consumption of SJB or IPM. Auto cut of dark current function activates.
"Power OFF Mode" : Power of MCU and circumferential circuit is cut for minimizing electricity consumption. Operation stops.
The explanation - The auto cut of dark current
Before delivering to customer | Fuse switch OFF |
•All door close & RKE door lock or Constant switch state (Auto cut of dark current scenario starts.) -After "sleep" state is for 20 min. -SJB power down(SJB dark current : 200 μA) and cutting power of Lamp/Body Load/Wake up |  |
After delivering to customer | Fuse switch ON |
•All door close & Constant switch state : C_BAState=OFF (Auto cut of dark current scenario starts.) -After "sleep" state is for 20 min. -SJB power down(SJB dark current : 200 μA) and cutting power of Lamp Load •In case RKE door lock : C_BAState=ON & Trunk SW=CLOSE (Auto cut of dark current scenario starts.) -After "Sleep" state 35s~65s (Waiting time of other unit : 30~60s + SJB sleep counts 5s) -SJB Powerdown(SJB dark current : 200 μA) and cutting power of Lamp Load |  |
Problem when mode switch setting is wrong
: If a fuse switch is set to OFF(Before delivering to customer) by a customer or technician and auto cut function of dark current activates, below problems may happen.
Symptom | Related part |
•Door lock/unlock, trunk open don't activate by RKE. (Wakeup of each module don't activate.) | BCM |
•Digital clock is reset.(Memory is reset.) | Digital clock |
•Setting value of audio(Volume, Frequency setting) is reset. (Memory is reset.) | Audio |
*If fuse switch OFF(before delivering to customer) is set, power of BCM, Digital clock and audio is shut off.
