Body Electrical System

Description and Operation

3steps
~18min
2/5difficulty
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Description

Body Control Module (BCM) Function
No Item Description
1 Washer-linked wiper
  • If the washer switch is pressed for 0.06~0.2 seconds with the vehicle mode in IGN2, the wiper relay turns on 0.3 ± 0.1 seconds after the washer turns on, and then the wiper relay turns off 0.7 ± 0.1 seconds later.
  • If the washer switch is pressed for more than 0.2 seconds with the vehicle mode in IGN2, the wiper relay turns on 0.3 ± 0.1 seconds after the washer turns on, and then the wiper relay turns off 2.5~3.8 seconds (wiper operates 2-3 times) after the washer turns off.
2 MIST-linked wiper
  • If the wiper mist switch is pressed for 0.7 seconds with the vehicle mode in IGN2, the wiper relay turns on, and then turns off 0.7 seconds later.
  • If the wiper mist switch is pressed for more than 0.7 seconds with the vehicle mode in IGN2, the wiper relay turns on, and then turns off 0.7 seconds after the wiper mist switch is released.
3 Variable INT wiper
  • If the INT wiper switch is turned on with the vehicle mode in IGN2, the INT wiper operates intermittently (10 ~ 2.2 s) according to the INT volume setting.
4 Rear window heater timer
  • If the heater switch is turned on with the vehicle mode in IGN ON and the generator running, the heater relay turns on for 20 minutes.
  • If the heater switch is pressed again, or if the generator mode is turned off while the heater is on, the heater relay turns off.
5 KEY Inter Lock
  • If the KEY INTER LOCK switch is off with the vehicle in IGN1 ON or ACC ON mode, the key solenoid output turns on and prevents key removal.
6 Shift Interlock
  • If the brake switch is on when the vehicle mode is IGN1 ON and the shift lever is in P, the shift interlock solenoid turns on to release the shift lever.
7 Trunk release
  • The trunk release relay turns on for 0.2±0.02 seconds when the trunk TX signal is received.
  • If the trunk opener switch is turned on when all doors are unlocked, the trunk release relay turns on for 0.2±0.02 seconds. (However, the trunk opener switch is ignored in ARMWAIT, ARM, REARM or ALARM modes.)
  • If the trunk opener switch in the cabin is turned on, the trunk release relay turns on for 0.2±0.02 seconds. (However, the trunk release relay is NOT turned on when the vehicle speed exceeds 5 km/h, or when the vehicle is in ARMWAIT, ARM, REARM or ALARM mode.)
8 Power window timer
  • The power window indicator relay turns on when the vehicle mode switches to IGN ON.
  • When the vehicle mode switches from IGN ON to OFF, the power window relay turns on for 30 seconds.
  • If a door is opened during the 30-second period of the power window relay being on, the power window relay turns off immediately.
  • If a door is open and the vehicle mode switches from IGN ON to OFF, the power window relay turns off immediately.
9 Driver seat belt reminder
  • If the seat belt is not fastened, the indicator comes on when the ignition is first turned on, and goes off when the seat belt is fastened.
  • If the vehicle speed exceeds 20 km/h with the seat belt unfastened, the indicator flashes and the buzzer sounds for 100 seconds.
  • If the vehicle speed exceeds 20 km/h after the seat belt was fastened and then unfastened, the indicator flashes and the buzzer sounds for 100 seconds. (Reminder)
  • If the seat belt is fastened or the vehicle mode is switched to IGN OFF within 100 seconds while the buzzer sounds, the indicator flashes and the buzzer turns off.
  • If the vehicle mode is switched to IGN ON with the seat belt unfastened, and the vehicle speed exceeds 20 km/h while the indicator is on, the indicator flashes and the buzzer sounds for 100 seconds.
10 Passenger seat belt reminder
  • If there is no occupant in the passenger seat, the system operates as if the seat belt is fastened.
  • If the seat belt is not fastened, the indicator comes on when the ignition is first turned on, and goes off when the seat belt is fastened.
  • If the vehicle speed exceeds 20 km/h with the seat belt unfastened, the indicator flashes and the buzzer sounds for 100 seconds.
  • When the vehicle speed exceeds 20 km/h after the seat belt was fastened and then unfastened, the indicator flashes and the buzzer sounds for 100 seconds. (Reminder)
  • If the seat belt is fastened or the vehicle mode is switched to IGN OFF within 100 seconds while the buzzer sounds, the indicator flashes and the buzzer turns off.
  • If the vehicle mode is switched to IGN ON with the seat belt unfastened, and the vehicle speed exceeds 20 km/h while the indicator is on, the indicator flashes and the buzzer sounds for 100 seconds.
11 Rear seat belt reminder
  • If the seat belt is not fastened, the indicator comes on for 35 seconds when the ignition is first turned on, then goes off when the seat belt is fastened.
  • If the vehicle speed exceeds 20 km/h with the seat belt unfastened, the indicator flashes and the buzzer sounds for 35 seconds.
  • If the vehicle speed exceeds 20 km/h after the seat belt was fastened and then unfastened, the indicator flashes and the buzzer sounds for 35 seconds. (Reminder)
  • If the seat belt is fastened or the vehicle mode is switched to IGN OFF within 35 seconds while the buzzer sounds, the indicator flashes and the buzzer turns off.
  • If the vehicle mode is switched to IGN ON with the seat belt unfastened, and the vehicle speed exceeds 20 km/h while the indicator is on, the indicator flashes and the buzzer sounds for 35 seconds.
12 KEY IN Warning
  • If the driver door is opened with the KEY IN, the buzzer sounds continuously at 1-second intervals.
  • The buzzer turns off if KEY OUT or the door is closed while the buzzer is sounding.
13 Parking brake warning
  • If vehicle speed exceeds 5 km/h while the vehicle mode is IGN1 and the parking brake is applied, the buzzer sounds until the parking brake is released. (The buzzer activates 0.6 seconds after the condition is met and deactivates 0.4 seconds after it is cleared, sounding intermittently at 1-second intervals until the parking brake is released.)
14 Room Lamp Fade-Out
  • If a door is opened with the vehicle mode in IGN OFF, the room lamp turns on. If the door is then closed, the room lamp remains ON for 30 seconds and then turns off. (Dimmer: 2 ± 0.2 sec.)
  • If the door remains open, the room lamp remains on for 20 minutes and then turns off. (Dimmer: 2 ± 0.2 sec.)
15 KEY HOLE Illumination
  • Key Hole Illumination Lamp: The lamp turns on when the door is opened while the vehicle mode is in IGN1 OFF, and the key hole illumination lamp is on. It turns off 30 seconds after the door is closed.
  • If the vehicle mode is switched to IGN1 ON while the key hole illumination lamp is on, the lamp turns off immediately.
  • If the vehicle mode is switched to ARMWAIT while the key hole illumination lamp is on, the lamp turns off immediately.
16 Tail Lamp Auto Off
  • If the tail switch is changed from OFF to ON, the tail lamp relay is turned on.
  • If the tail switch is OFF, the tail lamp relay is turned off.
  • If the KEY IN switch is OFF and the tail switch is ON, and the driver's door is opened while the KEY IN switch is ON and the tail switch is ON, the tail lamp relay is turned off. (Auto OFF)
  • If the KEY IN switch is turned ON after Auto OFF, the relay is turned on. The tail lamp relay does not turn on even if the driver's side door is opened and closed.
17 Headlamp Follow-Me
  • If the vehicle mode is changed from IGN1 to IGN1 OFF and the headlamp is turned on by the headlamp switch or auto light, the headlamp remains on.
  • The headlamp turns off under any of the following conditions.15 seconds after the driver's door is opened and closed.The headlamp or auto light is not turned on.If the driver's door remains open for more than 5 minutes.20 minutes after the vehicle mode is changed from IGN1 ON to IGN OFF.If the TX lock signal is received twice while the H/Lamp is on.
18 Headlamp LOW/HIGH Beam
  • If the low beam headlamps are on with the headlamp switch or auto light function on, and the high beam switch is turned on (momentary), the high beam headlamps turn on.
  • The high beam headlamps can only be turned off by the headlamp switch.
19 Low Beam Headlamp
  • The high beam headlamps are activated only when the headlamp switch is on and the vehicle mode is in IGN2 ON.
  • The switch is used to turn off the high beam headlamps when they are on.
20 Front Fog Lamp
  • If the front fog lamp is turned on while the tail lamp is on, the front fog lamp turns on.
  • If the front fog lamp switch is turned off while the front fog lamp is on, the lamp turns off.
  • If the low beam headlamps are turned on while the front fog lamps are on, the front fog lamps also turn on.
  • If the front fog lamp switch is turned off while the front fog lamp is on, the lamp turns off.
21 Automatic Light Control
  • If the auto light sensor detects a light-on condition, the lights turn on after 2.5 seconds.
  • If the sensor detects a light-off condition, the lights turn off after 2.5 seconds.
  • If the sensor detects the tail lamp on condition, only the tail lamp turns on. If the sensor detects the headlamp on condition, the tail lamp and headlamp turn on.
  • When the headlamp is turned on, the tail lamp and headlamp turn on regardless of the on/off state of the tail switch.
22 Daytime Running Lamps (DRL)
  • The DRL lamp turns on when the engine is started.
  • The DRL lamp turns off when the low beam headlamps or front fog lamps are turned on.
23 Headlamp Welcome
  • If the vehicle mode is switched to KEY OFF, all doors are closed and locked, and the headlamp is on (headlamp switch or AUTO switch + nighttime), then the RKE unlock is activated and the headlamp turns on for 15 seconds.
24 Tail Lamp Linkage
  • When the vehicle mode is switched to ACC ON, the auto light sensor reflects the light level.
  • If the auto light ambient light level is in the tail lamp ON state for more than 2.5 seconds, the ON signal is sent.
  • If the auto light ambient light level is in the tail lamp OFF state for more than 2.5 seconds, the OFF signal is sent.
25 DPAS
  • If the shift lever is moved to the R position while the vehicle mode is IGN1 ON, the buzzer sounds after 0.5 seconds.
  • The warning level is displayed in the cluster, and the buzzer sounds according to the warning condition.
26 Normal/ARMWAIT/Relock Mode
  • If the TX lock signal is received with the KEY IN switch removed from the cylinder and all doors closed, the all-door lock signal is output. When all door lock switches are locked, the hazard lamp flashes once and the vehicle enters SECURITY mode after the ARMWAIT time (30 sec.) has elapsed.
  • If the TX lock signal is received while any door, the hood, or the trunk is open, only the lock signal is output. The hazard lamp does not flash and the vehicle does not enter security mode.
  • If none of the doors is opened or KEY IN is not detected within 30 seconds after receiving the TX unlock signal, the vehicle returns to security mode.
27 Security Indicator Control
  • If the vehicle is in ARMWAIT mode when KEY OUT, the indicator remains on. The indicator flashes at intervals when the vehicle is in any mode other than ARMWAIT. (Flashing interval: 2 sec. OFF, 0.3 sec. ON)
28 Alarm Condition
  • If an alarm trigger condition is detected, the start inhibit is activated to prevent engine start and the alarm is activated.
29 DISARM/Alarm Deactivation Condition
  • If the TX UNLOCK/LOCK switch signal is received, the unlock/lock signal is output for 0.5 seconds, and START INHIBIT is deactivated.
  • If the KEY IN switch is on, the IGN1 switch is on, the IGN2 switch is on, and the alternator is on for 30 seconds, the start lock is released and the vehicle mode switches to DISARM.
30 RESET
  • If the battery is disconnected while the alarm is being armed and then reconnected, the alarm is also armed again.
  • If the battery is disconnected while the vehicle is in ARM mode and then reconnected, the vehicle remains in ARM mode.
31 Central Door Lock/Unlock
  • If the driver/passenger door lock/unlock KEY switch is turned on for 3 seconds, the lock/unlock signal is output to all doors for 0.5 seconds.
  • If the TX lock/unlock signal is received, the lock/unlock signal is output to all doors for 0.5 seconds.
  • If the driver door lock switch (power window) is in the lock/unlock position, the lock/unlock signal is output to all doors for 0.5 seconds.
32 Auto Door Lock
  • If the vehicle is in IGN1 ON mode, the alternator is on, and the vehicle speed exceeds 15 km/h, all doors lock within 1.5 seconds. (However, if all doors are already locked, or in case of failure of all doors, the all-door lock function is not performed.)
  • If any door is unlocked after locking under the above condition, the lock command is performed 3 times (at 1 second intervals). A door that is not locked during the 3 attempts is ignored.
  • The auto door lock function does not activate in the event of unlocking due to a collision.
33 Automatic Door Unlock
  • If KEY OFF follows KEY IN, all doors are unlocked. (However, if all doors are already unlocked, the unlock command is not performed.)
34 Driver Door Unlock Switch Synchronized Auto Unlock
  • If all doors are closed and the driver door unlock switch is changed from locked to unlocked, all door unlock signals are output once for 0.25 seconds.
35 IGNITION KEY REMINDER This function is not activated if the vehicle speed exceeds 3 km/h.
  • If the ignition key is on, the driver door switch is opened, and the driver door unlock state becomes locked, all doors are unlocked for 1 second after a 0.5 second delay.
  • IGNITION ON, door switch assist and door unlock assist. When the state becomes locked, all doors are unlocked for 1 second after a 0.5 second delay.
  • If the driver door switch is closed within 0.5 seconds, the driver door unlock state changes from UNLOCK to LOCK. When the vehicle is in IGN KEY ON mode, all doors are unlocked only once for 1 second.
  • If the unlock condition is met, unlocking is performed even if the condition is not maintained for 0.5 seconds.
36 Passive Key Reminder
  • This function is not activated if the vehicle speed exceeds 3 km/h.
  • If a KEY Reminder signal is received from the SMK, all door unlock commands are output for 1 second.
  • If the door remains locked even though the unlock command is output for 1 second as described above, unlocking is attempted up to 3 times (excluding the 1st output) (interval 1 s: 0.5 s on/off).
37 Emergency Door Unlock
  • Unlocking is performed each time an ACU signal is received while the IGN switch is on. The unlock output continues for the set time even if the vehicle mode is switched from IGN KEY ON to OFF.
  • If the driver/assistant/rear door lock switch is switched from unlock to lock after unlocking is performed, the unlock command is performed again for 5 seconds.
  • The auto door lock function does not activate in the event of unlocking due to a collision.
38 HBA (High Beam Assist)
  • If the headlamp high beam switch is on in automatic switching night mode, HBA mode is activated.
  • In HBA mode, when an oncoming vehicle or a preceding vehicle is detected (input signal from LDWS), the headlamp high beams are turned off.
  • If no oncoming or preceding vehicle is detected, the headlamp high beams are turned on automatically.
39 FOLD / UNFOLD
  • Folding/unfolding is performed when the fold/unfold switch is activated.
  • If the automatic switch is activated, folding/unfolding is performed automatically under any of the following conditions.
  1. When RKE lock/unlock is performed.
  2. When passive lock/unlock is performed.
  3. When an approach/departure signal from the smart key is detected.

Communication Network Diagram
Abbreviation Description
ACU Airbag Control Unit
ADM Assist Door Module
B_CAN Body Controller Network
BCM Body Control Module
BSD Blind Spot Detection
C_CAN Chassis Controller Area Network
CLU Cluster Module
DATC Dual Automatic Temperature Control
DDM Driver door module
ESC Electronic Stability Program
Emergency Call Engine Control System
LKAS Lane Keeping Assist System
M_CAN Multimedia Controller Network
MDPS Motor Driven Power Steering
P_CAN Power Train Controller Area Network
PSM Power Seat Module
CAC Steering Wheel Angle Sensor
SJB Smart Junction Box
SMK Smart Key Unit
PAS Park Assist System
TCU Transmission Control Unit
SCP Tire Pressure Monitoring System
VDC Vehicle Dynamic Control
TMU Telematics System
ABS Anti-Lock Braking System (ABS)

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