FRONT BODY CONTROL MODULE (FBCM) INSPECTION


id094000002100

1.  Remove the fuse box cover. (See RELAY AND FUSE BLOCK REMOVAL/INSTALLATION.)

2.  Remove the front body control module (FBCM) from the fuse box. (See FRONT BODY CONTROL MODULE (FBCM) REMOVAL/INSTALLATION.)

3.  Verify that the voltages of each of the terminals are as indicated in the Terminal Voltage Table (Reference). (See Terminal Voltage Table (Reference))

•  If the voltage is not as specified in the terminal voltage table (reference), inspect the parts under Inspection item(s) and related wiring harnesses.
―  If the system does not work normally even though the inspection items or related wiring harnesses do not have any malfunction, replace the front body control module (FBCM).


Terminal Voltage Table (Reference)

ac5wzw00000886

Terminal

Signal

Connected to

Measurement conditions

Voltage (V)

Inspection item(s)

1A
Power supply
HAZARD 25 A fuse
Under any condition
B+
•  HAZARD 25 A fuse
•  Battery
1B
Power supply
HAZARD 25 A fuse
Under any condition
B+
•  HAZARD 25 A fuse
•  Battery
1C
Ignition power supply
•  Climate control unit
•  Seat warmer control unit
•  A/C relay
•  PTC heater*6
Ignition switched ON (engine off)
B+
•  Climate control unit
•  Seat warmer control unit
•  A/C relay
•  PTC heater*6
Ignition switched off
1.0 or less
1D
Signal ground
Body ground
Under any condition
1.0 or less
Body ground
1E
Rear turn light (RH) control
•  Rear turn light (RH)
•  Side turn light (RH)
Ignition switched ON (engine off)
Turn switch at right turn light position
1.0 or less Û B+
•  Rear turn light (RH)
•  Side turn light (RH)
Turn switch is in position other than above
1.0 or less
1F
1G
Front turn light (RH) control
Front turn light (RH)
Ignition switched ON (engine off)
Turn switch at right turn light position
1.0 or less Û B+
Front turn light (RH)
Turn switch is in position other than above
1.0 or less
1H
1I
License light control
TNS relay
Light switch at TNS position
B+
TNS relay
Light switch at OFF position
1.0 or less
1J
1K
1L
Horn relay control
•  Horn relay
•  Clock spring
Horn switch not pressed
B+
•  Horn relay
•  Clock spring
Horn switch pressed
1.0 or less
1M
Headlight relay (LO) control
•  Headlight LO relay (halogen type)
•  Headlight LO relay (LH) (discharge type)
Light switch at HEAD position
1.0 or less
•  Headlight LO relay (halogen type)
•  Headlight LO relay (LH) (discharge type)
Light switch is in position other than above
B+
1N
1O*7
Theft-deterrent horn input signal
Rear body control module (RBCM)
M-MDS is connected and theft-deterrent is sounded using data monitor function
1.0 or less
Rear body control module (RBCM)
M-MDS is connected and theft-deterrent is not sounded using data monitor function
B+
1P
Rear window defroster relay control
Rear window defroster relay
Ignition switched ON (engine off)
Rear window defroster switch OFF
B+
Rear window defroster relay
Rear window defroster switch ON
1.0 or less
1Q*1
Headlight cleaner motor control
Headlight cleaner motor
Ignition switched ON (engine off) and light switch at HEAD position
Turn front washer switch ON 2 times within 2 s
B+→ 1.0 or less
Headlight cleaner motor
No operation
1.0 or less
1R*7
Theft-deterrent horn power supply
R.WIPER 15 A fuse
Under any condition
B+
•  R.WIPER 15 A fuse
•  Battery
1S*1
Headlight cleaner power supply
H/CLEAN 20 A fuse
Under any condition
B+
•  H/CLEAN 20 A fuse
•  Battery
1T*7
Theft-deterrent horn output signal
Theft-deterrent horn
M-MDS is connected and theft-deterrent is sounded using data monitor function
B+
Theft-deterrent horn
M-MDS is connected and theft-deterrent is not sounded using data monitor function
1.0 or less
2A
Interior light power supply
ROOM 15 A fuse
Under any condition
B+
•  ROOM 15 A fuse
•  Battery
2B
Front turn light (LH) control
Front turn light (LH)
Ignition switched ON (engine off)
Turn switch at left turn light position
1.0 or less Û B+
Front turn light (LH)
Turn switch is in position other than above
1.0 or less
2C*2
Running light control
Running light (LH, RH)
Ignition switched ON (engine off) and light switch OFF
Running light illuminates
B+
Running light (LH, RH)
Running light turns off
1.0 or less
2D
Rear turn light (LH) control
•  Rear turn light (LH)
•  Side turn light (LH)
Ignition switched ON (engine off)
Turn switch at left turn light position
1.0 or less Û B+
•  Rear turn light (LH)
•  Side turn light (LH)
Turn switch is in position other than above
1.0 or less
2E*9
LIN communication
Current sensor
Terminal used for communication therefore determination based on terminal voltage is not possible.
2F
2G*3
LIN communication
Auto-light sensor/rain sensor
Terminal used for communication therefore determination based on terminal voltage is not possible.
2H
LIN communication
DC-DC converter
Terminal used for communication therefore determination based on terminal voltage is not possible.
2I
CAN_L
CAN system related module
Terminal used for communication therefore determination based on terminal voltage is not possible.
2J*5
LIN communication
Climate control unit
Terminal used for communication therefore determination based on terminal voltage is not possible.
2K
CAN_H
CAN system related module
Terminal used for communication therefore determination based on terminal voltage is not possible.
2L
CAN_L
CAN system related module
Terminal used for communication therefore determination based on terminal voltage is not possible.
2M
Ignition power supply
C/U IG1 15 A fuse
Ignition switched ON (engine off)
B+
•  C/U IG1 15 A fuse
•  Related wiring harness
Ignition switched off
1.0 or less
2N
CAN_L
CAN system related module
Terminal used for communication therefore determination based on terminal voltage is not possible.
2O
2P
CAN_H
CAN system related module
Terminal used for communication therefore determination based on terminal voltage is not possible.
2Q
Brake fluid level switch signal
Brake fluid level sensor
Ignition switched ON (engine off)
Brake fluid level is less than MIN (brake fluid level sensor ON)
1.0 or less
Brake fluid level sensor
Brake fluid level is MIN or more (brake fluid level sensor OFF)
Wave pattern (See Pattern 1.)
2R
CAN_H
CAN system related module
Terminal used for communication therefore determination based on terminal voltage is not possible.
2S*8
Washer level switch signal
Washer fluid-level sensor
Ignition switched ON (engine off)
Washer level is less than MIN (washer fluid-level sensor ON)
1.0 or less
Washer fluid-level sensor
Washer level is MIN or more (washer fluid-level sensor OFF)
Wave pattern (See Pattern 1.)
2T*6
PTC heater signal
PTC heater
Terminal used for communication therefore determination based on terminal voltage is not possible.
2U
Ignition power supply
Start stop unit
Ignition switched ON (engine off)
B+
Start stop unit
Ignition switched off
1.0 or less
2V
Headlight relay (LO) control (discharge type)
Headlight LO relay (RH)
Light switch at HEAD position
1.0 or less
Headlight LO relay (RH)
Light switch is in position other than above
B+
2W
Headlight (LO) switch signal
Start stop unit
Light switch at HEAD position
1.0 or less
Start stop unit
Light switch at OFF position
B+
2X
Headlight relay (HI) control
Headlight HI relay
Headlight at HEAD position and dimmer switch at LO position
B+
Headlight HI relay
Headlight at HEAD position and dimmer switch at HIGH or passing position
1.0 or less
2Y
Windshield wiper (LO) switch signal
Start stop unit
Windshield wiper switch at ON position
1.0 or less
Start stop unit
Windshield wiper switch at OFF position
B+
2Z
Blower motor relay control
Blower relay
Ignition switched ON (engine off)
1.0 or less
Blower relay
Ignition switched OFF (LOCK)
B+
2AA
Autostop switch signal
Windshield wiper motor
Ignition switched ON (engine off)
Wipers are stopped in position other than park
B+
Windshield wiper motor
Wipers are stopped in park position
1.0 or less
2AB*4
Front fog light relay control
Front fog light relay
Light switch at HEAD position
Front fog light switch OFF
B+
Front fog light relay
Front fog light switch ON
1.0 or less
3A
Wiper power supply
WIPER 20 A fuse
Under any condition
B+
•  WIPER 20 A fuse
•  Battery
3B
Wiper power supply
WIPER 20 A fuse
Under any condition
B+
•  WIPER 20 A fuse
•  Battery
3C
Windshield wiper motor (HI) control
Windshield wiper motor
Ignition switched ON (engine off)
Windshield wiper switch at HI position
B+
Windshield wiper motor
Windshield wiper switch at OFF position
1.0 or less
3D
Power ground
Body ground
Under any condition
1.0 or less
Body ground
3E
Windshield wiper motor (HI) control
Windshield wiper motor
Ignition switched ON (engine off)
Windshield wiper switch at HI position
B+
Windshield wiper motor
Windshield wiper switch at OFF position
1.0 or less
3F
Windshield washer motor control
Washer motor
Ignition switched ON (engine off)
Windshield washer switch ON
B+
Washer motor
Windshield washer switch OFF
1.0 or less
3G
Windshield wiper motor (LOW) control
Windshield wiper motor
Ignition switched ON (engine off)
Windshield wiper switch at LOW position
B+
Windshield wiper motor
Windshield wiper switch at OFF position
1.0 or less
3H
Rear window washer motor control
Washer motor
Ignition switched ON (engine off)
Rear window washer switch ON
B+
Washer motor
Rear washer switch OFF
1.0 or less
3I
Windshield wiper motor (LOW) control
Windshield wiper motor
Ignition switched ON (engine off)
Windshield wiper switch at LOW position
B+
Windshield wiper motor
Windshield wiper switch at OFF position
1.0 or less
3J
Interior illumination power supply
•  Glove compartment light
•  Selector illumination
•  Hazard warning switch
•  Climate control unit*5
•  Audio unit
•  Clock spring
Light switch at TNS position
B+
•  Glove compartment light
•  Selector illumination
•  Hazard warning switch
•  Climate control unit*5
•  Audio unit
•  Clock spring
Light switch at OFF position
*10
3K
Power supply
HAZARD 25 A fuse
Under any condition
B+
•  HAZARD 25 A fuse
•  Battery
3L
Power supply
HAZARD 25 A fuse
Under any condition
B+
•  HAZARD 25 A fuse
•  Battery

*1  :With headlight cleaner system
*2  :With running light system
*3  :With auto wiper/ auto light system
*4  :With front fog light system
*5  :With manual air conditioner
*6  :With PTC heater
*7  :With theft-deterrent system
*8  :With washer fluid-level sensor
*9  :With i-ELOOP
*10  :The measured voltage changes according to the tester specification, therefore determination based on terminal voltage is not possible.

Inspection Using an Oscilloscope (Reference)


Pattern 1

ac5jjw00000385
•  Terminal:
―  Brake fluid level switch signal: 2Q (+) Û ground (-)
―  Washer level switch signal: 2S (+) Û ground (-)
•  Oscilloscope setting: 2 V/DIV (Y), 1 ms/DIV (X), DC range