Suzuki XL7 2007 Service Manual page 2324

9B-3 Lighting Systems:
Interior Lighting Systems Description and
Operation
Interior Lamps
The interior lamps consist of 2 groups, those which can
dim from the instrument panel (I/P) dimmer switch and
those that can not dim.
Courtesy/Illuminated Entry Lamps
The following lamps may be manually turned ON by
placing the interior lamp switch in the ON position, or by
opening a door while the switch is in the AUTO position.
• The dome lamp
• The liftgate lamps
• Courtesy/map lights
The courtesy lamp supply voltage circuit of the body
control module (BCM) supplies battery positive voltage
to the dome lamp, the liftgate lamps, and the map lamps.
When any door is opened, the door jamb switch contacts
close providing a door open input to the BCM. The BCM
then provides a ground to the interior lamps with the
switch in the AUTO position. The interior lamps receive a
ground at G401 with the switch in the ON position.
NOTE
If the liftgate is opened after all the modules
go to sleep, the dome light will not come on.
The liftgate ajar switch input to the BCM will
not wake up the BCM once it has gone to
sleep, so the dome light will not come on.
Once the BCM gets an input to wake it up,
from remote keyless entry (RKE) or a door
handle, the dome light will turn on when the
liftgate is opened.
If the driver inadvertently leaves any interior lamp ON,
the BCM will turn it OFF after a 20 minute time-out.
The courtesy lamps will turn OFF immediately if the
ignition switch is turned to the ON position or
approximately 20 seconds after all doors are closed.
Keyless Entry Interior Illumination
When the body control module (BCM) receives a door
unlock command from the remote keyless entry (RKE)
transmitter, the BCM will flash the park lamps several
times, illuminate the courtesy and park lamps, and
illuminate the low beam headlamps at low intensity. The
lamps will remain on until the ignition key is turned from
the OFF position, a RKE door lock command is received,
or after an approximate 20 second delay.
Schematic and Routing Diagram
Interior Lamps Dimming
This group includes lamps which may dim. This group
may use a combination of vacuum fluorescent (VF)
illumination and incandescent lamps.
• HVAC control module, head assembly
• Rear HVAC control module, head assembly
• Radio
• Rear seat Audio
• The instrument panel cluster (IPC)
• The PRNDL lamp, with the exception of the current
gear select position
• Power window switches
• Various switches
When the ignition switch is turned to the ON position, the
VF display, radio, turns ON at maximum brightness.
When the park lamps are ON, all incandescent back
lighting turn ON at the dimming level indicated by the
instrument panel (I/P) dimmer switch. At the same time
all VF displays dim to match the indicated dimming level.
When the headlamp switch is placed in the PARK
position, the park lamp supply voltage circuit provides an
input to the body control module (BCM). The BCM then
supplies voltage to the I/P dimmer switch through the I/P
dimming lamps control circuit. The setting of the I/P
dimmer switch determines the amount of voltage that the
I/P dimmer switch supplies to the BCM through the I/P
dimming lamps low reference circuit. The BCM then
sends a pulse width modulation (PWM) voltage to all the
interior lamps. All the VF and incandescent back lighting
lamps are provided a specific voltage and are then
grounded. When the headlight switch is turned to the
park lamp or headlamp position, all incandescent back
lighting turn ON at the dimming level indicated by the I/P
dimmer switch. When the I/P dimmer switch is moved
from MIN to MAX, all VF displays, as well as all
incandescent back lighting respond from minimum
intensity to maximum brightness in response to the I/P
dimmer switch.
Inadvertent Power
The body control module (BCM) used in this vehicle
controls the lighting system through circuits that enable
the interior lamps. The BCM opens these enabling
circuits shortly after the ignition switch is turned OFF with
no lamp switch activity. If the ignition switch is turned to
any position other than OFF, or if a lamp switch is
activated during this period, the timer will reset itself.