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:

Courtesy/Illuminated Entry: 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 FRT CTSY relay coil and the RR CTSY relay coil. 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 driver door module (DDM) in order to indicate that a door is open. The DDM then sends a class 2 message to the rear integration module (RIM) in order to indicate which door is open. When the ambient light sensor indicates low light conditions, the RIM activates the INT LP relay in order to provide battery positive voltage to the interior courtesy lamps. When any front door is opened, the RIM will energize the FRT CTSY relay grounding the overhead courtesy/reading lamps, the foot well lamps, and all door courtesy lamps to G301. The driver door module will also illuminate all backlit components in the driver's door at full brightness. The ignition key cylinder lamp will also illuminate. When any rear door is opened, the RIM will energize both the FRT CTSY relay and the RR CTSY relay. The rear courtesy/reading lamps then illuminate, since they are grounded to G402. The driver door module will also illuminate all backlit components in the driver's door at full brightness. The ignition key cylinder lamp will also illuminate. When all of the doors have been closed, the courtesy lamps will remain illuminated for approximately 25 seconds. If the ignition switch is placed in the RUN position, or the interior lamp switch is placed in the OFF position before the end of the elapsed period the lamps will deactivate immediately, except for the driver's door switch backlighting. The courtesy lamps will also deactivate immediately if an all door lock command is received with all of the doors closed.

Ignition Key Cylinder Lamp: When the interior lamps are activated by the RCDLR, by opening any door, or by placing the interior lamp switch in the ON position, the ignition key cylinder lamp will illuminate. The RIM sends a class 2 message to the instrument panel integration module (IPM) to activate the ignition key cylinder lamp.

IP Compartment Lamp: The RIM energizes the interior lamp relay which provides battery positive voltage to the instrument panel (IP) compartment lamp. When the IP compartment is opened, its switch closes to provide a ground circuit and the IP compartment lamp illuminates.

Keyless Entry Illumination: When the 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 ambient light sensor is indicating low light conditions. The interior lamp switch must not be in the OFF position. The RIM will then activate the interior lamp relay, providing battery positive voltage to the interior lamps, and activate both the FRT CTSY relay and the RR CTSY relay. The RIM will keep all of the courtesy lamps on for approximately 40 seconds. If the door locks are activated to the LOCK position the courtesy lamps will deactivate immediately. The courtesy lamps will also turn off immediately 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. The 3 positions of the interior lamp switch in the overhead console are ON, AUTO, and OFF. The ON and OFF positions are inputs to the IPM. When the interior lamp switch is placed in the ON position, the interior lamp switch on signal circuit is grounded to G402. The IPM then sends a class 2 message to the RIM to activate all courtesy lamps. When the interior lamp switch is in the OFF position, the courtesy lamps will not illuminate under any circumstances, except post SIR deployment.

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: When the supplemental inflatable restraint (SIR) system is activated, all courtesy lamps will illuminate. The inflatable restraint sensor and diagnostic module (SDM) sends a class 2 message to the RIM. The ignition switch must be in the RUN position. The RIM will activate both the FRT CTSY relay and the RR CTSY relay approximately 15 seconds after airbag deployment, regardless of ambient light status or the position of the interior lamp switch. 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. The vanity mirror lamp may be dimmed by the sliding switch next to the mirror. The switch is a potentiometer in which the resistance varies as the switch is moved. As the resistance of the potentiometer increases, the vanity lamp receives less voltage. The vanity lamp then becomes dimmer.

Interior Lamps Dimming

Interior lamp dimming are lamps that may be dimmed by operating the IP Dimmer switch. This group consist of the following lamps:

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 ambient light sensor indicates low light conditions, all incandescent back lighting and vacuum fluorescent (VF) displays turn on at the dimming level indicated by the IP 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) provides battery positive voltage to the PRK LP relay coil. 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-1circuit of the DIM. With the park lamps on, the DIM sends pulse width modulated (PWM) voltage to the backlight lamps control circuit in response to an input from the instrument panel integration module (IPM). The potentiometer of the IP 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 and at G201. When the IP 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 driver door module (DDM). The DDM sends a simple bus interface (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 interior lamp relay control output is still active, and the ignition switch is turned to the OFF position. The RIM timer is set to 3 minutes until the vehicle mileage is above 15 miles. At the end of the designated time, the RIM will deactivate the interior lamp relay, the FRT CTSY relay, and the RR CTSY relay disabling the interior lamps. This feature will be cancelled if any power mode other than OFF becomes active. The timer will reset if any of the doors are opened prior to the timer expiring. The timer will not reset if the rear compartment lamp switch, any of the reading lamp switches, the IP compartment lamp switch, or any of the vanity lamp switches are in the ON position when the timer expires.