Interior Lamps

INTERIOR LIGHTING SYSTEMS DESCRIPTION AND OPERATION

INTERIOR LAMPS
The interior lighting consist of the following three groups.

This first group includes lamps that may not be dimmed.
- Courtesy/Reading Lamps
- Dome lamps
- I/P Courtesy lamps and Rear Compartment Courtesy Lamps
- Vanity Mirror Lamps

COURTESY/READING LAMPS
The second group include lamps that may be manually turned on by placing the interior lamp switch in the ON position, or by opening a door.
- Roof Rail/Reading Lamps
- I/P Courtesy Lamps
- Dome Lamps

The courtesy lamps, may be manually turned on by placing the interior lamp switch in the ON position, or by opening a door. The sunload sensor assembly must indicate low light conditions for the interior lamps to operate by opening a door, then the following scenarios will occur. When a front door is opened, the I/P courtesy lamps, all door and the overhead console courtesy lamps turn on. If a rear door is opened, only the courtesy lights illuminate. After all the doors have been closed the courtesy lamps will remain illuminated approximately 25 seconds after the last door closes. When the sunload sensor assembly indicates daylight conditions, the interior courtesy lamps will not illuminate at all.

The INT LP fuse in the fuse block - rear supplies battery positive voltage to the normally open switch contacts of the interior lamp relay. The INT LP fuse also supplies battery positive voltage to the interior lamp relay control circuit. The door modules communicate on a simple bus interface (SBI). When you open any door, the switch contacts of the door jamb close. When a door open input is grounded, that door module sends a message to the drivers door module (DDM) in order to indicate that a door is open. The DDM sends a class 2 message to the rear integration module (RIM) in order to indicate which door is open. The RIM activates the INT Lamp relay in order to provide battery positive voltage to the interior courtesy lamps. Depending on which doors are opened, front or rear, the proper interior courtesy lamps illuminate. The RIM provides a pulse width modulated ground to all interior courtesy lamps for the interior lights theater dimming feature. Some of the courtesy lamps are also used as reading lamps, each reading lamp may be manually turned on or off using it's own respective switch.

The courtesy lamps will normally turn off using the theater dimming feature. The courtesy lamps will also turn off immediately if an all door lock command is received with all the doors closed, or if the ignition switch is turned to either the ON or RUN position.

After the deployment of the supplemental inflatable restraint (SIR) system, all courtesy lamps will illuminate after an approximate 15 second delay period. The courtesy lamps can only be deactivated, or turned off, after the ignition switch is placed in the OFF position.

KEYLESS ENTRY INTERIOR ILLUMINATION
When the remote control door lock receiver module (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 has been received. The RIM must have inputs that indicate that the ignition switch is OFF, all the doors are closed, and the sunload sensor assembly is indicating low light conditions. The RIM will then activate the INT Lamp relay, providing battery positive voltage and also a pulse width modulated (PWM) ground to the interior lamps. The RIM will keep the courtesy lamps on approximately 40 seconds and 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 ON or RUN position the courtesy lamps will deactivate immediately. When the sunload sensor assembly indicates daylight conditions, the interior courtesy lamps will not illuminate at all.

I/P COMPARTMENT LAMP
The RIM energizes the INT Lamp relay which provides battery positive voltage to the I/P compartment lamp. When the I/P compartment is opened, its switch closes to provide a ground circuit and the I/P compartment lamp illuminates.

REAR COMPARTMENT COURTESY LAMP
The RIM energizes the INT Lamp relay which provides battery positive voltage to the rear compartment courtesy lamp. When the rear compartment is opened, its switch closes to provide a ground circuit and the rear compartment lamp illuminates.

VANITY MIRROR LAMPS
The RIM energizes the INT 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 LAMPS DIMMING
The third group includes lamps which may be dimmed. This group may use a combination of vacuum fluorescent (VF) illumination and of incandescent lamps.
- Door switches and the window switches
- Driver information center (DIC)
- Heated seat switches
- Headlamp switch
- HVAC control head assemblies
- Radio
- Instrument panel cluster (IPC)
- Steering wheel control switches

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 assembly indicates low light conditions, 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 fuse block - rear 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 control circuit. The DIM also provides ground to the PRK LP relay control circuit. When the DIM energizes the PRK LP relay, current flow from switch goes through the DIMR fuse to the incandescent dimming circuit of the DIM. With the park lamps on, the DIM sends proportional voltage to the circuit in response to an input from the HVAC control module with C67 or instrument panel module (IPM) with CJ2. The potentiometer of the I/P dimmer switch receives a reference voltage and ground from the HVAC control module or IPM. The potentiometer is an input to the HVAC control module or IPM. When the driver selects a dimming setting, the HVAC control module or IPM responds with a message to the DIM indicating this setting. When the I/P dimmer switch is moved from MIN to MAX, all vacuum fluorescent (VF) displays, as well as all incandescent backlighting respond from minimum intensity to maximum brightness in response to the I/P dimmer switch.

The incandescent backlighting for the doors also operate in response to a class 2 message regarding dimming intensity. The HVAC control module or IPM sends the message to the driver door module (DDM). The DDM sends an SBI message regarding dimming intensity to all the other door modules. 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 INT LP 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 20.3-24.7 km (12.6-15.4 mi). 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 remote control door lock receiver (RCDLR) is activated.