Interior lighting

The interior lights comprise the functions

Front interior light (with interior lamp and IB button, reading lights, direct light)
Rear interior light (with interior lamp and selector switch, reading lights, direct light)
Footwell light, front left
Footwell light, front right
Lamp, rear left
Lamp, rear right
Lighting for make-up mirror, left
Lighting for make-up mirror, right
Lighting for make-up mirror, rear
Glovebox light
Front centre armrest lamp

Brief description of components

Power module

The power module monitors the battery charge level and the open-circuit current consumption of the car. In addition, the boot lid lock is controlled via the power module. Information is received and sent via the data bus K-CAN PERIPHERALS.

Light module

The light module controls and monitors the vehicle lights. Information is received and sent via the data bus K-CAN SYSTEM.

Interior lamp, front (E34) and rear (E108)

The interior lamps are fitted in the roof and contain the functions:

Interior lamp (bulb): the front and rear interior lamps are activated in parallel by the power module. In the rear interior lamp (E108), a diode is fitted in the IB and VA cables in the conducting direction.
Reading light (bulb): the reading lights left and right in the interior lamps are switched on and off individually with a switch.
Direct light (light emitting diode): the light emitting diodes are activated in parallel by the light module.
Button: The (IB) button in the front interior lamp is used for the functions ”switch on”, ”switch off” and ”automatic control” for both interior lamps.

Footwell lights, front left (E61) and right (E62)

The footwell lights are fitted in the side walls. The footwell lights are controlled in the same way as the front inside light.

Lights, rear left (E39) and right (E40)

The lights on the L version are fitted in the door sills. The light emitting diodes are controlled by the light module.

Lighting for make-up mirror, front left (E35) and right (E36)

The lighting for the make-up mirrors is fitted in the sun visor. The lamps are activated/deactivated by switches when the covers are slid open or closed.

Lighting for make-up mirror, rear centre (E144)

The lighting for the rear centre make-up mirror is fitted in the roof. The bulb is switched on when the button on the mirror is pressed and the mirror folded out. The bulb is switched off when the mirror is folded in.

Glovebox light

The glovebox light is fitted to the front right in the glovebox. The glovebox light is switched on by a switch when the glovebox lid is opened.

Front centre armrest lamp

The centre armrest lamp is fitted in the compartment below the centre armrest. The light emitting diode is controlled by the power module.

Main functions

Switching the interior lights

Switching with remote control: If the independent heating is switched on using the radio-control key of the remote control, the front and rear interior lights and the footwell lights are switched on via the CAS, the CAN-PERIPHERALS bus and the power module for 3 seconds. Switching on the interior lights confirms that the independent heating has been switched on.

Switching with key: The IB button in the front interior lamp can be used to select the functions ”switch on”, ”disconnect” and ”automatic control” of the passenger-compartment lighting.

Off: The interior lighting is switched off permanently by pressing the button for approx. 3 seconds.

On: The interior lighting is switched by touching the button. The automatic control function is reactivated.

The button in the rear interior lamps can be used independently of this to switch to ”continuous light ON/OFF” because the bulb is supplied additionally with AV.

Brightness control of the instrument lighting and direct light

The basic brightness of the instrument lighting is measured in the instrument cluster. The basic brightness can be reduced by 10% by means of the interior lighting dimmer potentiometer in the light switch. Parallel to this, the brightness of the direct light is changed.

Control of the interior lights

The automatic control of the interior lights is dependent on a number of switch-on and switch-off conditions.

Switch-on conditions:

At least one door is opened.
The central locking system (ZV) is unlocked using the radio-control key. IB is then switched on for 20 seconds.
The radio-control key performs a (codable) search function. Repeated pressing of the ”lock ” key switches on the interior lights for 8 seconds if the vehicle was locked or secured less than 10 seconds beforehand (no antirepeat device integrated).
Terminal R is switched off and the light (terminal 58) is switched on or was switched on in the last 32 seconds at least once. The interior lights are switched on for 20 seconds.
The independent heating has been switched on using the remote control. To confirm the switching on, the passenger-compartment lighting goes on for 3 seconds.
The central locking system has been unlocked by activation of the crash sensor (emergency lighting).

Switch-off conditions:

All doors are closed and terminal R or terminal 15 On.
All doors are closed, cutoff is with a delay of 20 seconds.
Terminal R OFF (if terminal 58 was active at least once within the last 32 seconds at least once) with deactivation delay of 20 seconds.
IB on using the remote control (search function) with 8 seconds.
IB on using the remote control ”unlock” with 20 seconds.
After 16 minutes when a door is held permanently open.
All doors are closed and the central locking system is locked.
IB on as acknowledgement for independent heating on with 3 seconds.

if the interior lights are switched off using the button when a door is open, when this door is closed once the automatic function takes effect once again.

Soft ON/OFF function

The Soft ON/OFF function gradually increases the brightness of the passenger-compartment lighting on switching on from 10% to 96% and reduces it on switching off from 96% to 10%. If the passenger-compartment lighting is switched on using the IB button on the front interior lamp, the Soft ON/OFF function at the front and rear comes into effect. If the button on the rear interior lamp is pressed, the function is switched off and the rear passenger-compartment lighting is switched to full brightness. The function can be deactivated via coding.

Load cutout

The following lights can be switched on when the vehicle is parked:

Reading light
Glovebox light
Luggage compartment lights

To ensure the vehicle battery is not discharged when the lights are switched on permanently, the power module switches off all lights of the vehicle approx. 15 minutes after the ignition has been switched off (terminal R Off, IB, VA_K, VA_D off).

The lights are switched on again when terminal R or terminal 15 are switched on again or when there is a signal change on the power module, for example, opening a door, opening the engine bonnet, unlocking a door.

Interior lights in an emergency

If the ISIS system detects a crash, IB is switched on permanently after approx. 1 minute by means of the Soft ON/OFF function for emergency lighting of the passenger compartment to support any rescue work that might be required. It can only be switched off using the button in the front interior lamp by setting the function to Off or resetting the switch-on status of ISIS.