Description
Smart Junction Box(SJB)
1.

General function : Interior Junction Box + some functions of BCM

It controls loads with CAN communication and IPS.

2.

Main function

A.

Low speed CAN communication(100 kbps)

B.

Self diagnostics(Lamp open/short)

C.

Fail safe(When MCU/CAN is fail, Head lamp / Tail lamp directly drive)

D.

Protection of bulb over-voltage(PWM function)

E.

Cut of Over-load and Short : PCL(Program Current Limit)

Auto cut system of dark current
1.

Description : It cuts automatically power to be provided with load for reducing useless dark current according to vehicle state.

2.

SJB had 3 modes, "Normal Mode", "Sleep Mode", "Power Off Mode". Auto cut of dark current practice in "Sleep Mode".

A.

"Sleep" condition : IG OFF, constant input switch, CAN network doesn't activate.

B.

"Sleep" resolutive condition : Any switch inputs, CAN network activates, KEY ON, IGN ON

C.

"Power OFF" condition : The setting time of timer which is used by cutting a load power expires.

D.

"Normal Mode" : SJB function normally activates.

E.

"Sleep Mode" : It is low power mode and activates for reducing electricity consumption of SJB or IPM. Auto cut of dark current function activates.

F.

"Power OFF Mode" : Power of MCU and circumferential circuit is cut for minimizing electricity consumption. Operation stops.

3.

The explanation - The auto cut of dark current

Before delivering to customer

Mode Switch

• 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

Mode Switch

• 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 

4.

Problem when mode switch setting is wrong

: If a mode 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 mode switch OFF(before delivering to customer) is set, power of BCM, Digital clock and audio is shut off.

Яндекс.Метрика