Interior Lighting Systems
Interior Lighting Systems Description and Operation
Interior Lamps
The interior lighting consists of 2 groups. The first group includes lamps that may not be dimmed.
* Courtesy/illuminated entry lamps
* Dome lamps
* Map lamps
* Reading lamps
* Vanity mirror lamps
Courtesy/Illuminated Entry Lamps
The courtesy/illuminated entry lamps, may be manually turned ON or OFF by toggling the interior lamp switch. If an outside door handle is lifted and 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 body control module (BCM) will then turn them OFF through the theater dimming feature. 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 open/ajar door switches are connected directly to the BCM. These control the lamp illumination linked to the door and luggage compartment open/ajar switch signals. For all vehicles, the passenger front and both rear door latch switches are on one circuit that is also an input to the BCM.
When the driver unlocks the vehicle using the drivers door lock the BCM quickly fades the courtesy lamps from OFF to ON. After the door has been closed the courtesy lamps will remain ON, for approximately 15 seconds and then will slowly fade from ON to OFF. If the vehicle is locked, or the ignition switch is turned to the RUN or CRANK position the courtesy lamps will turn OFF immediately.
All the courtesy lamps are controlled and receive voltage from the BCM. Voltage for the courtesy lamp supply voltage circuit is from the F5-15A interior lights/turn right front fuse in the instrument panel fuse block. The BCM monitors the ambient light via the sunload sensor and uses the information provided by it to enable or disable the operation of the courtesy/illuminated entry lamps. The BCM will enable the operation of the courtesy/illuminated entry lamps at low levels of ambient light and disable the operation of the courtesy/illuminated entry lamps in high levels of ambient light.
Keyless Entry Interior Illumination
When the driver uses the remote function transmitter to unlock the vehicle or to activate the panic function, the BCM will turn ON the courtesy lamps and keep them ON for approximately 30 seconds. When the driver uses the remote function transmitter to lock the vehicle, the BCM will turn OFF the courtesy lamps immediately. If the ignition switch is turned on to the RUN or CRANK position the courtesy lamps will slowly fade from ON to OFF.
Vanity Lamps
The inadvertent power supply voltage circuit of the body control module (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.
Reading Lamps
The inadvertent power supply voltage circuit of the body control module (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.
Battery Rundown Protection/Inadvertent Power
The body control module (BCM) inadvertent power supply voltage circuit provides battery positive voltage to all of the interior reading lamps, visor vanity mirror lamps, and cargo lamps if equipped. 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.
Interior Lamps Dimming
The second interior lighting group includes lamps which may be dimmed. This group may use a combination of vacuum fluorescent (VF) illumination, LED illumination and incandescent lamps.
When the ignition switch is turned to the RUN position, the radio VF display turns ON. When the park lamps are ON, all incandescent and LED back lighting turn ON at the dimming level previously set by the driver using the + or - buttons on the headlamp/dimming switch. At the same time all VF displays dim to match the indicated dimming level. The headlamp/dimming switch is an input to the body control module (BCM). When the driver selects a dimming setting by depressing the + or - buttons on the headlamp/dimming switch all incandescent back lighting lamps are provided with a specific voltage. When the interior lamp dimming is increased from the minimum to maximum level, all VF displays as well as all incandescent back lighting respond from minimum intensity to maximum intensity.
The following components have back lighting when the park lamps are ON:
* Instrument panel cluster (IPC)
* Window/mirror/door lock switch
* Headlamp switch
* PRNDL lamps
* Object detection enable/disable switch (multifunction center console switch)
* Traction control switch (multifunction center console switch)
* Steering wheel control switches
* Dome lamp front
* Rear seat entertainment control panel
* Radio and HVAC controls and display
* SIC
The interior lamp dimming can be controlled by the BCM which outputs a pulse width modulated signal to components which are directly wired to it, or by a control module which has a display attached or directly wired to it.
The following components have their light dimming controlled by the BCM :
* PRNDL lamps
* Window/mirror/door lock switch
* Headlamp switch
* Object detection enable/disable switch (multifunction center console switch)
* Traction control switch (multifunction center console switch)
* Steering wheel control switches
* Dome lamp front
The following components control their own light dimming :
* Instrument panel cluster (IPC)
* Rear seat entertainment control panel
* Radio and HVAC controls and display
* Secondary Driver Information Display