Interior Lamps
The interior Lamps consist of two groups. The first group are those lamps which
may not be dimmed. The second group includes lamps that may be dimmed.
Courtesy/Illuminated Entry Lamps
Courtesy/illuminated entry lamps are lamps that may be illuminated by opening
a door, manually operating a switch, or through a remote control door lock receiver
(RCDLR) command. This group consists of the following lamps:
• | The courtesy/reading lamps |
• | The door courtesy lamps |
• | The vanity mirror lamps |
• | The IP compartment lamp |
• | The rear compartment lamp |
The INT LP fuse in the rear fuse block supplies battery positive voltage to
the normally open switch contacts of the INT LP relay. The rear fuse block supplies
battery positive voltage to the interior lamp relay coil. When a door is opened, the
switch contacts of the door jamb close. When a door open input is grounded, that door
module sends a class 2 message to the rear integration module (RIM) in order
to indicate which door is open. When the sunload sensor indicates low light conditions,
the RIM activates the interior lamp relay in order to provide battery positive voltage
to the interior courtesy lamps. The RIM provides a pulse width modulated (PWM) ground
to the interior courtesy lamps on the front and rear interior lamp control circuits
for theater dimming. The RIM pulses the on time of the ground circuit between 0-100%
at a frequency of approximately 100 hertz. By decreasing the on time percentage
of the controlled ground circuit the intensity of the lamps will decrease. The RIM
will illuminate these lamps under various conditions which will be described in the
following information.
Courtesy/Illuminated Entry: When any door is opened, all of
the courtesy lamps will illuminate. The lamps will remain illuminated as long as either
door remains open or the inadvertent power/battery run down protection causes the
outputs to be turned off. When a front door is opened, the driver door module will
also illuminate all backlit components in the driver's door at full brightness. The
lamps will remain illuminated as long as either door remains open or the inadvertent
power/battery run down protection causes the outputs to be turned off. The courtesy
lamps will remain illuminated approximately 25 seconds after the all of the
doors have been closed. At this time the RIM will fade the lamps from full intensity
to off in 3-5 seconds. The courtesy lamps will turn off using the theater
dimming feature if the ignition switch is placed in the RUN position. The courtesy
lamps will turn off immediately if an all door lock command is received with all the
doors closed.
Courtesy/Illuminated Entry, Limo/Hearse Vehicles: When a front
door is opened, the front door, and the overhead console courtesy lamps will illuminate.
The driver door module will also illuminate all backlit components in the driver's
door at full brightness. The lamps will remain illuminated as long as either door
remains open or the inadvertent power/battery run down protection causes the outputs
to be turned off. When a rear door is opened, the rear courtesy/reading lamps and
rear door courtesy lamps will illuminate. The lamps will remain illuminated as long
as either door remains open or the inadvertent power/battery run down protection causes
the outputs to be turned off. The courtesy lamps will remain illuminated approximately
25 seconds after all of the doors have been closed. At this time the RIM will
fade the lamps from full intensity to off in 3-5 seconds. The courtesy
lamps will turn off using the theater dimming feature if the ignition switch is placed
in the RUN position. The courtesy lamps will turn off immediately if an all door lock
command is received with all the doors closed. When the hearse cargo/rear door is
opened the reverse lamps will also illuminate.
Exit Lighting: The RIM will activate all courtesy lamps when
it receives a class 2 message from the instrument panel cluster (IPC) indicating
that the ignition key has been removed from the lock cylinder. The ambient light status
must be NIGHT, and all of the doors must be closed. The RIM will theater dim the interior
lamps after 20-25 seconds. During exit lighting feature the RIM will
also request that the drivers door module illuminate the driver door switch backlighting
at full intensity for 20-25 seconds. If the key is placed back into the
lock cylinder before the lamps have dimmed, the RIM will immediately activate the
theater dim feature. For limo/hearse vehicles the RIM only requires that the front
doors are closed for exit lighting. The RIM will activate only the front courtesy
lamps for the limo/hearse.
I/P Compartment Lamp: The RIM energizes the interior lamp relay
which provides battery positive voltage to the instrument panel compartment lamp.
When the I/P compartment is opened, its switch closes to provide a ground circuit
and the I/P compartment lamp illuminates.
Keyless Entry Illumination: When the remote control door lock
receiver (RCDLR) receives a door unlock command from the keyless entry transmitter,
the RCDLR will send a class 2 message to the rear integration module (RIM)
indicating that an UNLOCK command was received. The RIM must have inputs that indicate
that the ignition switch is OFF, all the doors are closed, and the sunload sensor
is indicating low light conditions. The RIM will then activate the interior lamp relay,
providing battery positive voltage and also a PWM ground to the interior lamps. The
RIM will keep the courtesy lamps on for approximately 40 seconds and then turn
them OFF through the theater dimming feature. If the door locks are activated to the
LOCK position the courtesy lamps will deactivate immediately. The courtesy lamps will
turn OFF using the theater dimming feature if the ignition switch is placed in the
RUN position.
Manual Interior Lighting: The interior lamps may also be illuminated
manually in any ambient light status. When the I/P dimmer switch/interior lamp switch
is rotated clockwise into the interior lamp ON position the contacts in the switch
close, grounding the interior lamp switch on signal circuit of the Instrument panel
integration module (IPM). The IPM then sends a class 2 message to the RIM to
activate all courtesy lamps. When the I/P Dimmer switch is placed out of the interior
lamp ON position, the RIM will immediately turn OFF the interior lamps.
Panic Interior Illumination: The RIM will activate all courtesy
lamps when the RCDLR receives a panic signal from the keyless entry transmitter, the
power mode is OFF, and the ambient light status is NIGHT. The RIM will activate all
courtesy lamps and request that the driver door module illuminate the driver door
switch backlighting at full intensity. The interior lamps will remain illuminated
for 30 seconds or until the RIM received a door unlock message.
Reading Lamps: The RIM energizes the interior lamp relay which
provides battery positive voltage to the reading lamps. By placing a reading lamp
switch in the ON position the switch closes and provides a path to ground and the
reading lamp illuminates.
Rear Compartment Lamp: The RIM energizes the interior lamp relay
which provides battery positive voltage to the rear compartment lamp. When the rear
deck lid opens, the rear compartment lamp switch in the latch assembly closes to provide
a ground for the rear compartment lamp.
Supplemental Inflatable Restraint (SIR) Interior Illumination: Approximately 0.5 seconds after activation of the supplemental inflatable restraint
(SIR) system, all courtesy lamps will illuminate. When the SIR system is activated
the inflatable restraint sensor and diagnostic module (SDM) sends a class 2
message to the RIM. If the ambient light sensor status is night the RIM will activate
the interior lamps approximately 15 seconds after airbag deployment. The interior
lamps will remain illuminated until there is a change in power mode.
Vanity Mirror Lamps: The RIM energizes the interior lamp relay
which provides battery positive voltage to the vanity mirror lamps. When the vanity
mirror cover on the sunshade is opened, its switch closes to provide a ground circuit
and the vanity lamp illuminates.
Interior Lamp Dimming
Interior lamp dimming are lamps that may be dimmed by operating the I/P Dimmer
switch. This group consist of the following lamps:
• | The door switches and the window switches |
• | The HVAC control head assembly |
• | The instrument panel cluster (IPC) |
• | The headlamp switch assembly |
• | The hazard warning switch |
• | The shift indicator lamp |
• | The driver information center (DIC) switches |
• | The traction control switch |
• | The heated seat and the memory seat switches |
• | The steering wheel controls |
When the ignition switch is turned to the ON position, the vacuum fluorescent
(VF) displays turn on at maximum brightness. When the park lamps are ON and the sunload
sensor indicates low light conditions, all incandescent back lighting and vacuum fluorescent
(VF) displays turn ON at the dimming level indicated by the I/P dimmer switch. The
rear fuse block supplies battery positive voltage to the normally open switch of the
PRK LP relay. The dash integration module (DIM) supplies battery positive voltage
to the PRK LP relay coil controlled positive voltage circuit. The DIM also provides
ground to the control circuit of the PRK LP relay coil. When the DIM energizes the
park lamp relay, current flows through the PRK LP relay switch to the DIMR fuse to
the instrument panel lamp fuse supply voltage 1 circuit of the DIM. With the
park lamps on, the DIM sends proportional voltage to the circuit in response to an
input from the instrument panel integration module (IPM). The potentiometer of the
I/P dimmer switch receives a reference voltage and ground from the IPM. The potentiometer
is an input to the IPM. When the driver selects a dimming setting, the IPM responds
with a message to the DIM indicating this setting. All vacuum fluorescent (VF) lamps
and all incandescent back lighting lamps have ground at G200, G201, and G302 for limo/hearse
vehicles. 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 IP dimmer switch. The instrument cluster
provides a 54 volt supply to the instrument panel integration module (IPM).
The supply circuit is used to power the HVAC vacuum fluorescent (VF) display. The
incandescent back lighting for the doors also operates in response to a class 2
message regarding dimming intensity. The IPM sends the message to the appropriate
door module regarding dimming intensity. The driver may select parade mode by manually
turning on the park lamps during daylight conditions. The front park lamp circuit
supplies voltage to the instrument panel cluster, radio and HVAC assembly for a park
lamp on input, and the displays will become full bright.
Battery Run Down Protection/Inadvertent Power
To provide battery run down protection, the interior lamps will be deactivated
automatically under certain conditions. The rear integration module (RIM) initiates
a 10 minute timer if the interior lamp relay control output is still active,
and the ignition switch is in the OFF position. The RIM timer is set to 3 minutes
until the vehicle mileage is above 22.5 KM (14 miles). At the end of
the designated time, the RIM will deactivate the interior lamp relay, disabling the
interior lamps. This feature will be cancelled if any power mode other than OFF becomes
active. The RIM will reset the timer if any interior lamp switch is turned ON, a door
is opened, or the RCDLR is activated.