Body Control Module (BCM): Overview Hyundai Elantra V

Function Description

1. General Function Condition In BATTERY ON and Tail Lamp is off state, if user turns on the Tail Lamp switch (Tail switch ON), Tail Lamps are turned on.

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1. Tail Auto Cut Function Condition The "Tail Auto Cut" strategy ensures that Tail lamps are turned off even if a driver forgets to turn them off. When the Tail lamp is turned on by Tail lamp switch, after key insertion, and if a user removes key and opens the driver side door (or vice versa), the Tail lamps are automatically turned off. While "Tail Auto Cut" function is active, if a user turns off the Tail lamp switch or inserts key, "Tail Auto Cut" function will be deactivated and Tail lamps can be turned on. NOTE: "Tail Auto Cut" state is memorized in ECU, so even if battery reset, this state is not erased. During the activation of Escort function, no Tail Auto Cut mode is possible and it is only after escort function deactivation that Tail Auto Cut mode can be applied. CAN signal Tail Activity Condition When tail lamp output condition is met, Tail Lamp activity CAN data (EXT Tail_Act & INT Tail Act) is also turned on. When tail lamp output condition is not met, Tail Lamp activity CAN data (EXT Tail Act & INT Tail Act) is also turned off. Internal signal Tail Activity Condition When tail lamp output is on, internal signal Tail Lamp activity (Tail Lamp) is also turned on. When tail lamp output is off, internal signal Tail Lamp activity (Tail Lamp) is also turned off.
2. HEAD LAMP CONTROL Overview Description This function describes the following features Turn on and off Head Lamp Low by Head Lamp Low Switch input. Turn on and off Head Lamp Low by Escort Function. Turn on and off Head Lamp Low by Auto Light Control Request. Turn on and off Head Lamp High by Head Lamp High Switch input. Turn on and off Head Lamp High and Low by Passing Switch Input. Output control of Head Lamp Low. Output control of Head Lamp High. Output control of Head Lamp High Indicator. Output control of Head Lamp control for CANADA DRL.

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1. Head Lamp Function Block diagram Head Lamp Function In/Out List FUNCTION REFERENCE Function Characteristics Name Hardware Label Spec. Designation Input Digital L_HeadLampLowSW Head Lamp Low Switch L_AutoLightSW Auto Light Switch L_HeadLampHighSW Head Lamp High Switch L_IGN1 Ignition1 power L_EC_DRL_OPT Dedicated DRL option Switch CAN Communication C_ALT_L Engine is running C_SMKRKECMD SMK RKE Command from Fob C_DRVDRSW Driver Side Door Open/Close Status C_PARKING BRAKE SW Parking Brake Switch Status C_CANADA_DRLSts DRL Option Switch C_D_DRL_Act Dedicated DRL ON/Off State C_HLampLOW_Act Head Lamp Low On/Off State C_HLampHIGH_Act Head Lamp High On/Off State Internal b_HeadAutoState Head Lamp Low On/Off request by Auto Light Control Module Internal b_KeyOff L_KeyIn == Off && L_ACC == Off && L_IGN1 == Off && L_IGN2 == Off b_C_IGNSW Same value with C_IGNSW (refer ECU spec.) b_IGN on: b_C_IGNSW == IGN ON off: b_C_IGNSW == KEY OFF || b_C_IGNSW == KEY IN || b_C_IGNSW ==ACC ON || b_C_IGNSW ==ST b_ACC on: b_C_IGNSW == ACC ON off: b_C_IGNSW == KEY OFF || b_C_IGNSW == KEY IN || b_C_IGNSW ==IGN ON || b_C_IGNSW ==ST b_START on: b_C_IGNSW == ST off: b_C_IGNSW == KEY OFF || b_C_IGNSW == KEY IN || b_C_IGNSW ==ACC || b_C_IGNSW ==IGN ON b_HeadLampHighSW This signal reserved for separated Head Lamp High input from Passing input b_PassingSW On:L_HeadLampHighSW==OnOff:L_HeadLampHighSW==Off b_HeadLampLowSWOn On: L_HeadLampLowSW == On || (b_HeadAutoState == On && (b_IGN == On || b_START == On)) Off: L_HeadLampLowSW == Off && b_HeadAutoState == Off b_LOCK P_RKECMD == Lock || C_SMKRKECMD == Lock || C_PassiveLock == Lock b_2LOCK b_LOCK counter b_Unlock b_RKEUnLock==On || C_SMKRKECMD == UnLock || C_PassiveUnlock== UnLock b_DRLOpt DRL Option Output Digital O_HeadLampLowCTRL Head Lamp Low Output Status (Active Low) Internal b_Escort Escort activation/deactivation Status b_HeadLampHighOutput On: C_HeadLampHighON = OnOff: C_HeadLampHighON = Off b_HeadLampLow Internal Head Lamp Low activity b_HeadLampHigh Internal Head Lamp High activity b_DRLOut DRL Option activation/deactivation Status CAN Communication C_CANADA_DRLON CANADA DRL ON Command C_D_DRL_ON DEDICATED DRL ON Command C_HeadLampLowON Head Lamp Low On/Off command C_HeadLampHighON Head Lamp High On/Off command C_EXTTailON EXTTail On/Off command
2. Head lamp low signal control Head Lamp Low control output is ON if HEAD LAMP LOW output is ON by 'Head Lamp Low switch ON ' or 'AUTO LIGHT function'. Head Lamp Low control output is OFF when HEAD LAMP LOW output is ON->OFF.
3. Head lamp high control Head Lamp High input and Head Lamp Passing input by M/F is Head Lamp High switch processing for single input same MULTI-FUNCTION WIRING DESCRIPTION as Head Lamp High switch only input. Head Lamp High Input When Head Lamp High switch ON that in IGN2 ON and Head Lamp Low control output is ON by IMP, Head Lamp High is consider as input. Head Lamp Passing Input When Head Lamp High switch ON that in IGN2 ON and Head Lamp Low control output is OFF, Head Lamp Passing is consider as input.
4. Multi-function wiring description

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1. Head Lamp Low Control In IGN terminal State (IGN ON), if turn on the Head Lamp LOW switch (Head Lamp Low switch ON), Head Lamp LOW outputs are turned on (Head Lamp Low ON). When Tail lamp Off and headlamp Off conditions are satisfied at the same time, Head Lamp LOW and Tail LAMP turned off simultaneous immediately.
2. Head Lamp High Control In IGN terminal State (IGN ON) and Head Lamp Low switch On (Head Lamp Low switch ON), if turn on the Head Lamp High switch (Head Lamp High switch ON), Head Lamp High Outputs are turned on (Head Lamp High ON).
3. Passing Control In IGN terminal State (IGN ON), If Head Lamp Passing switch Input (Head Lamp High switch ON & Head Lamp Low control OFF) is detected then Head Lamp High Output (Head Lamp High ON) are turned on and Head Lamp Low Output (Head Lamp Low ON) at the same time.
4. Canada DRL If alternator level is high (ALT L=On), BCM activates Canada DRL functionality and turns on the Head lamp high (CANADA DRL=On). Deactivation if: Head lamp low On request by Head lamp switch or auto light head lamp Low control or Head high On request by passing switch or Parking brake switch On
5. Escort Function After user generates the call of head lamp low light (Head Lamp Low switch On), if switch off ignition (IGN Off and START Off), and then keep Head Lamp Low Output On (Head Lamp Low ON) state during 20min. And after open and close driver side door (Driver door switch ON -> Driver door switch Off), user will have consequently lighting of head lamp low (Head Lamp Low ON) during only 30sec. During active "Escort Function", if receive Lock request 2 times (2 LOCK) or cancel the lighting request of head lamp low (Head Lamp Low switch Off & Auto Light switch Off), this function is released. Lock request counting for 2 times (2 LOCK) is each follow cases: RKE CMD == Lock SMK RKE CMD == Lock Passive Access Lock== Lock If open the Driver door (Driver door switch ON) or close (Driver door switch Off), former lock counter is cleared, and start new 2 times lock counting.
6. Head Lamp Welcome Function "Multifunction switch head lamp or auto light position and lock stated, if remote unlock, and then keep head lamp output on state during 15second. Lighting state, if remote lock and unlock, immediately light turn off." NOTE: While escort function is activated, Tail lamp is keeping the turn on state and does not go to Auto cut and after finish escort state and user removes key, it can go Auto cut mode. While the "Escort Function" is activated by 'Head Lamp Low Switch', if change from 'Head Lamp Low Switch' to 'Lamp Auto Switch', "Escort Function" is deactivated, because Lamp Auto mode is 'Lamp Off' condition. While the "Escort Function" is activated by 'Lamp Auto Switch', if change from 'Lamp Auto Switch' to 'Head Lamp Low Switch', "Escort Function" is keeping the activation state, because of 'Head Lamp On' condition. After IGN terminal off 20 minute timers is started, but as soon as door is opened and closed then 30sec timer is engaged.