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GF82.20-P-2020S Switching on/Off Rear Dome Lamp, Function



GF82.20-P-2020S Switching On/Off Rear Dome Lamp, Function







The lights have two functions:
- Illumination of the rear passenger compartment (rear dome lamp)
- Illumination of the rear vanity mirror (see vanity mirror)

They are actuated and switched on/off differently depending on the function.

The following always applies:
If the vanity mirror is folded down, the corresponding light always burns until it is switched off automatically 30 minutes after the last signal on the bus.

The switch-on/switch-off possibilities described here then have no effect.

Manually switching on/off the rear dome lamps:
When the rear dome lamp switch (N70s2) in the overhead control panel control module is actuated the interior and vanity mirror lamps (E15/10e2, E15/11e2) are faded on.
Fade-off is accomplished when the switch is actuated again or automatically to protect the battery 30 minutes after the last bus signal. If the lamps are switched on manually none of the automatic features described below are possible.

Prerequisites for automatic features
- automatic driving light circuit switched on on instrument cluster (A1) and
- door contact ON and OFF switch (N70s3) switched on (switch in the center position)
- light sensor has recognized night or:
- automatic driving light circuit switched off on instrument cluster (A1) and
- Door contact ON and OFF switch (N70s3) switched on (switch in the center position)

Automatic features for rear dome lamps (interior and vanity mirror lamps (E15/10e2, E15/11e2))
- The lamps are faded on when one of the rear doors is open. Switch-off is accomplished:
- With c.15 on: lamps are faded off immediately after closing the last front door or automatically 30 minutes after the last rear door was opened,
- with c.15 off: lamps are faded off 8 s after closing the last rear door.

- The rear dome lamps are faded on when the vehicle is. unlocked Switch-off is accomplished:
- Fade-off 30 s after unlocking
- The lamps are faded on when the ignition key is removed.

Switch-off is accomplished automatically according to the interior light shut-off delay time set in the instrument cluster (A1). (Possible settings are 0s, 5s, 10s, 15s and 20s.)

- If c.15 is switched on during an automatic active light function, the dome lamps are faded off immediately.
- If the prerequisites (door contact on/off switch position or light sensor information) change while an automatic feature is being performed, the change is taken into consideration immediately.
Example:
If the dome lamps are switched on because one of the rear doors is open and the light sensor information changes from "night" to "day", the dome lamps are faded off immediately. (Prerequisites: automatic driving light circuit switched on!)

ATA and taxi emergency alarm
In the event of an ATA or taxi emergency alarm the lamps are switched on immediately without fade-on.

Actuation
The lamps are actuated by the overhead control panel control module (N70). For this purpose the overhead control panel control module receives the following information:
- Brightness; for this purpose the automatic light switch daylight sensor (B32/1) is read in directly by the overhead control panel control module (N70),
- the status of the rear door contact switches (S17/5 and S17/6) is read in by the rear SAM control module (N10/8) and relayed on via the CAN bus (passenger compartment),
- the set interior light shut-off delay time is relayed to the overhead control panel control module by the instrument cluster (A1) via the CAN bus (passenger compartment).

Voltage too high/too low
If the voltage is too low the lamps are switched off immediately without fade-out. When the correct voltage returns the lamps are switched back on without fade-on.

In the event of an ATA or taxi emergency alarm the lamps are not switched off when the voltage is too high/too low.