Interior Lamps

The interior lamps consist of two groups. The first group are those lamps which may not be dimmed. The second group include 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 radio antenna module command. This group consist of the following lamps:

The rear integration module (RIM) controls battery positive voltage and ground to the interior courtesy lamps in the following manner. Battery positive voltage is supplied through the INTERIOR LAMP fuse to both the switch side and coil side feed of the interior lamp relay. The RIM provides a ground to the control circuit of the interior lamp relay during all power modes except when battery run down protection is active. With the interior lamp relay energized battery positive voltage is supplied to all the interior lamps in this group. The ground side circuits of the door, footwell and overhead courtesy lamps are controlled by a pulse width modulated (PWM) ground circuit of the RIM. 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. This effect is called theater dimming. The RIM will illuminate these lamps under various condition which will be described in the following information.

Courtesy/Illuminated Entry: Courtesy/illuminated entry occurs when any of the door control modules receive a discreate input from the door open switch located in the door latch assembly. The appropriate door control module sends a class 2 message to the RIM indicating a door is opened. If the ambient light status is NIGHT the RIM will illuminate the courtesy lamps. The lamps will remain illuminated for 25 seconds after all the doors are closed or until the ignition is placed in the ON position. At this time the RIM will fade the lamps from full intensity to off in 3-5 seconds by activating the theater dim feature.

Exit Lighting: Exit lighting is activated when the following conditions exists. The RIM 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 is NIGHT and all the doors are closed. At this time the RIM will illuminate the interior lamps. During this exit lighting feature the RIM will also request that the drivers door module illuminate the driver's door switch back lighting at full intensity. The RIM will theater dim the interior lamps after 20-25 seconds. If the key is place back into the lock cylinder before the lamps have dimmed, the RIM will immediately activate the theater dim feature.

Keyless Entry Illumination: Keyless entry illumination is activated when the radio antenna module detects a door UNLOCK command from the keyless entry transmitter. The radio antenna module will send a class 2 message to the RIM indicating that an UNLOCK command was received. The RIM will then activate the courtesy lamps if all the doors are closed, the ignition is in the OFF position and the ambient light status is NIGHT. The RIM will also send a class 2 message to the drivers door module (DDM) requesting for the drivers door switches to be illuminated at full intensity. The RIM will keep the lamps on 36-40 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 to the ON or RUN position the courtesy lamps will deactivate immediately.

Manual Interior Lighting: The interior lamps may also be illuminated manually in all ambient light conditions. When a vehicle occupant places I/P dimmer switch to the interior lamp ON position the contacts in the switch close, grounding the interior lamp input circuit of the dash integration module (DIM). With this input grounded the DIM sends a class 2 message to the RIM requesting the interior lamps illuminate. The RIM will ground the lamps as mentioned above. 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 Illumination:  If the radio antenna module detects a PANIC signal from keyless entry transmitter, the RIM will activate the interior lamps and request that the drivers door module illuminate the driver's door switch back lighting at full intensity. The interior lamps will remain illuminated for 30 seconds or until the radio antenna module detects a door UNLOCK message. At this time the RIM will active the theater dim feature.

Reading Lamps:  The reading lamps will operate in all ambient light conditions. The reading lamp switches are located in the courtesy/overhead reading lamp assembly. By pressing the overhead reading lamp switch the contacts in the switch close and provides a direct path to ground for the corresponding reading lamp. When the switch is pressed again the contacts open turning off the reading lamp.

Rear Compartment Lamp: The rear compartment lamp will operate in all ambient light conditions. When the rear deck lid opens the rear compartment lamp switch in the latch assembly closes to provide a direct path to ground for the rear compartment lamp. Closing the deck lid opens the contacts in the switch turning off the rear compartment lamp.

Supplemental Inflatable Restraint (SIR) Lighting: The RIM will provide interior lamp illumination in the event that an airbag has been deployed. Upon deployment of the airbag the SDM will send a class 2 message to the RIM. The RIM will activate the interior lamps approximately 15 seconds after the airbag deployment if the ambient light sensor status is NIGHT and the ignition is in the ON position. The interior lamps will remain illuminated until there is a change in the power mode.

Vanity Mirror Lamps: The vanity mirror lamps operate in all ambient light conditions. When the cover on the sunshade is opened, a switch internal to the sun shade closes to provide a direct path to ground. Closing the cover opens the contacts and turns off the vanity lamps.

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:

When the park lamp switch is in the ON position the dash integration module (DIM) energizes the park lamp relay. With the PRK LP relay energized, battery positive voltage is supplied through the LIC/DIMMING fuse to the instrument panel lamp fuse supply voltage-1 circuit of the DIM. Upon receiving this voltage supply the DIM requests the status of the ambient light sensor from the climate control panel (CCP). The CCP sends a class 2 message indicating a DAY or NIGHT status of the ambient light sensor. The DIM will default to NIGHT if the message is not received. If the status of the ambient light sensor is DAY then the interior back lighting will not be activated. The DIM also receives an input from the I/P dimmer switch. The DIM provides the I/P dimmer switch with a 5.0 volt reference voltage and ground. The I/P dimmer switch is a potentiometer that varies the input signal voltage to the DIM between 0.09V and 4.75V. This input determines the intensity level of the back lighting illumination. The driver may change intensity of the back lighting by positioning the I/P dimmer switch between the minimum and maximum settings. The DIM will default to full intensity if the input from the dimmer switch is not within the specified values. Upon receipt of all the fore mentioned information the DIM then sends a class 2 message to the CCP, IPC, radio and all the door modules indicating the ON/OFF status and intensity level of the back lighting. The CCP, IPC and radio incorporate vacuum fluorescent (VF) lamps are illuminated at full intensity with the ignition in the ON position. When the park lamps are active, the CCP, IPC and radio will adjust the VF lamp intensity as requested by the DIM by varying the pulse width modulation of the power feed circuit to the lamps. When the door control modules receive the class 2 message each door module will supply PWM voltage to the door switch LED's at the requested intensity. The DIM also supplies voltage to all the remaining lamps at the proper PWM voltage to achieve the requested intensity. The PRNDL incorporates LED lamps that are illuminated at full intensity with the ignition in the ON position. When the park lamps are active, the IPC will adjust the PRNDL LED intensity as requested by the DIM by varying the pulse width modulation of the LED dimming signal circuit to the lamps. All the interior black lighting lamps are permanently grounded and therefore illuminate.

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 radio antenna module is activated.