Interior Lamps
The interior lighting consist of the following 2 groups. This first group includes
lamps that may not be dimmed.
• | Courtesy/Illuminated entry lamps |
Courtesy/Illuminated Entry Lamps
The courtesy/illuminated entry lamps, may be manually turned on or off by placing
the interior lamp switch in the ON or OFF position. If an outside door handle is lifted
or a door is opened, the courtesy/illuminated entry lamps illuminate. After all the
doors have been closed the courtesy/illuminated entry lamps will remain illuminated
approximately 15 seconds. The courtesy/illuminated entry lamps will also turn
on prior to any door being opened, and remain illuminated approximately 40 seconds
when the driver removes the ignition key. When the driver places the dome lamp defeat
switch in the OFF position, the courtesy/illuminated entry lamps will be disabled.
The left and right front door courtesy lamps are controlled, and receive voltage
and ground from the drivers door module (DDM) and the passenger door module (PDM)
respectively. The body control module (BCM), DDM, and the PDM communicate through
class II serial data for the lamp illumination commands and the door ajar switches.
The remaining courtesy lamps are controlled and receive voltage from the BCM.
Voltage for the courtesy lamp supply voltage circuit and the backup lamp supply voltage
circuit is from the TBC B fuse in the instrument panel fuse block directly
through the BCM to these circuits. A short to ground on either of these circuits will
open the fuse. Ground is provided to the footwell lamps and all courtesy/reading lamps
at G203. Ground is provided to the right middle and right rear door at G306. Ground
is provided to the left middle and left rear door at G302.
Keyless Entry Interior Illumination
When the driver uses the door key in order to unlock the doors, the BCM receives
a door unlock signal. The BCM must have inputs that indicate that the ignition switch
is OFF, the courtesy lamp switch is OFF and all the doors are closed. The BCM will
then activate the interior lamps. The courtesy lamps will remain on, approximately
15 seconds after the door is closed. The BCM will then turn them off through
the theater dimming feature. If the door locks are activated to the LOCK position,
or if the ignition switch is turned to either the RUN or CRANK position the courtesy
lamps will turn off immediately.
When the driver uses the remote function actuator transmitter to unlock the
doors, trunk or presses the panic button, the BCM will keep the courtesy lamps on
approximately 40 seconds. When the driver uses the remote function actuator
transmitter to lock the doors, the BCM will keep the courtesy lamps on approximately
2 seconds. If the ignition switch is turned to either the RUN or CRANK position
the courtesy lamps will turn off immediately. The BCM will also keep the courtesy
lamps on approximately 40 seconds, after an alarm event is completed.
Vanity Lamps
The inadvertent power supply voltage circuit of the BCM provides battery positive
voltage to each vanity mirror lamp. When the vanity mirror cover on the sunshade is
opened, a switch closes to provide a ground circuit and the vanity lamp illuminates.
In the event that any of these lamps were to remain illuminated for a period of more
than 10 minutes with the ignition switch in the OFF position, the BCM will
deactivate the inadvertent power supply voltage circuit to prevent a total battery
discharge condition. Ground is provided to the vanity lamps at G203.
Reading Lamps
The inadvertent power supply voltage circuit of the BCM provides battery positive
voltage to the reading lamps. The reading lamps and switch are integral to the courtesy/reading
lamp assembly. When the switch is closed, voltage is supplied and the lamp illuminates.
In the event that any of these lamps were to remain illuminated for a period of more
than 10 minutes with the ignition switch in the OFF position, the BCM will
deactivate the inadvertent power supply voltage circuit to prevent a total battery
discharge condition. Ground is provided to the reading lamps at G203.
Battery Rundown Protection/Inadvertent Power
The BCM inadvertent power supply voltage circuit provides battery positive
voltage to all of the interior reading lamps, visor vanity mirror lamps, and the cargo
lamps. In the event that any of these lamps were to remain illuminated
for a period of more than 10 minutes with the ignition switch in the OFF position,
the BCM will deactivate the inadvertent power supply voltage circuit to prevent a
total battery discharge condition.
The BCM also utilizes the inadvertent power supply voltage circuit as a lamp
request when none of the lamps in the circuit are illuminated. When a lamp switch
is activated, the BCM receives the request for lamp illumination and switches to supplying
voltage to the inadvertent power supply voltage circuit.
Interior Lamps Dimming
The second group includes lamps which may be dimmed. This group may use a combination
of vacuum fluorescent (VF) illumination and incandescent lamps.
When the ignition switch is turned to the RUN position, the radio's vacuum fluorescent
(VF) displays turn on at maximum brightness. When the park lamps are on, all incandescent
back lighting turn on at the dimming level indicated by the I/P dimmer switch. At
the same time all vacuum fluorescent (VF) displays dim to match the indicated dimming
level. The panel dimmer switch potentiometer is an input to the BCM. When the driver
selects a dimming setting by moving the I/P dimming switch potentiometer, all incandescent
back lighting lamps are provided with a specific voltage. When the I/P dimmer switch
is moved from MIN to MAX, all vacuum fluorescent (VF) displays, as well as all incandescent
back lighting respond from minimum intensity to maximum brightness in response to
the I/P dimmer switch.
The following switches and components have back lighting when the park lamps
are on:
• | The instrument panel cluster (IPC) |
• | Window and heated seat switches |
• | Garage door opener switch |
• | Power take off (PTO) switch |
• | Headlamp leveling switch |
• | Rear wheel steering mode select switch |
• | Headlamp and panel dimmer switch |
• | Transfer case shift control switch |
• | Traction control switch |
• | Steering wheel control switches |
The left and right front door switch illumination is controlled, receives voltage
and ground from the drivers door module (DDM) and the passenger door module (PDM)
respectively. The radio is also a class II module and has full control of its illumination.
The BCM, DDM, PDM, and radio communicate through class II serial data for the lamp
illumination commands
The I/P cluster illumination lamps receive voltage and are controlled by the
BCM on the instrument panel lamps dimming supply voltage circuit. Ground for the instrument
panel lamps is at G203.
The various switches, HVAC control assembly, and the PRNDL lamps receive voltage
and are controlled by the BCM on the instrument panel lamps dimming control circuit.
Ground for the rear window switches is at G302 and G306. Ground for the traction control
switch, steering wheel controls, and the rear window/wiper switch is at G108. Ground
for the remaining switches is at G203.
The following indicators receive voltage from the BCM and are controlled by
ground or from various modules:
• | Rear wheel steering mode select switch indicators |
• | Fog lamp switch indicators |
• | All multifunction accessory switch indicators |
• | Traction control switch traction control OFF indicator |
• | Transfer case control switch position indicators |
Ground/control for the indicators is from various modules or ground. Voltage
for the LED dimming supply circuit, instrument panel lamps dimming control circuit
and the instrument panel lamps dimming supply circuit is from the TBC A fuse
in the instrument panel fuse block directly through the BCM to these circuits. A short
to ground on only the instrument panel lamps dimming control circuit will open the
fuse.
The modules controlling the above indicators are as follows:
• | Rear wheel steering control module |
• | Electronic suspension control module |
• | Transfer case shift control module |
• | Body control module (BCM) |