Automatic dome lamp actuation, function - GF82.20-P-3004A

MODEL 203 

Fig 1: Automatic Dome Lamp Actuation Function Diagram

Function sequence when unlocking driver's door or entire vehicle 

Function requirements:

• Vehicle locked
• The dome lamp switch (N70s3) is switched to position "Automatic actuation ON".
• It is dark.

The vehicle is unlocked selectively or globally. The overhead control panel control unit (N70) is actuated by central locking via the Controller Area Network bus Class B (interior) (CAN-B) (1) with the message "driver door unlocked" or "vehicle unlocked". The overhead control panel control unit starts checking the automatic light switch daylight sensor (B32/1) and recognizes that it is dark. The overhead control panel control unit triggers the automatic dome lamp actuation and simultaneously switches on the front dome lamp (N70e1) integrated in the overhead control panel control unit and the dome lamp (E15/3e3) integrated in the rear dome lamp (E15/3) dimmed.

The front dome lamp (N70e1) and the rear dome lamp (E15/3) are switched off dimmed, when:

• no door is opened after unlocking after 30 s
• a door is opened after unlocking and the door is not closed again after 5 min.
• the driver door or the entire vehicle is locked after 3 s

Function sequence when opening a door 

Function requirements:

• Vehicle locked
• The dome lamp switch (N70s3) is switched to position "Automatic actuation ON".
• It is dark.

The rear SAM control unit with fuse and relay module (N10/2) monitors the following door contact switches: left front door contact switch (S17/3), right front door contact switch (S17/4), left rear door contact switch (S17/5) (except model 203.7), and right rear door contact switch (S17/6) (except model 203.7). The rear SAM control unit with fuse and relay module (N10/2) recognizes by the changed switch position of one of the door contact switches that a door was opened and actuates the overhead control panel control unit (N70) via the Controller Area Network bus Class B (interior) (CAN-B) (1) with the message "front door open" or "rear door open". The overhead control panel control unit (N70) starts checking the automatic light switch daylight sensor (B32/1) and recognizes that it is dark.

The overhead control panel control unit (N70) triggers the automatic dome lamp actuation and switches the lamps on dimmed if the following conditions apply:

• The front dome lamp (N70) integrated into the overhead control panel control unit when the driver or passenger door is opened
• The dome lamp (E15/3e3) integrated into the rear dome lamp (E15/3) when one of the rear doors is open (except model 203.7)

The front dome lamp (N70e1) and the rear dome lamp (E15/3) are switched off dimmed, when:

• the door is not closed after opening, after 5 min
• the door is closed, after 8 s

Function sequence when removing electronic key 

Function requirements:

• Vehicle is unlocked and all doors are closed.
• The dome lamp switch (N70s3) is switched to position "Automatic actuation ON".
• The transmitter key (A8/1) is inserted in the electronic starter switch of the EIS control unit (N73).
• It is dark.

The EIS control unit (N73) recognizes that the transmitter key (A8/1) is no longer inserted in the EIS control unit (N73) and actuates the overhead control panel control unit (N70) via the Controller Area Network bus Class B (interior) (CAN-B) (1) with the message "key removed". The overhead control panel control unit (N70) starts checking the automatic light switch daylight sensor (B32/1) and recognizes that it is dark. The overhead control panel control unit triggers the automatic dome lamp actuation and simultaneously switches the following lamps on dimmed:

• The front dome lamp (N70e1) integrated in the overhead control panel control unit (N70)
• The dome lamp (E15/3e3) integrated in the rear dome lamp (E15/3)

The front dome lamp (N70e1) and the rear dome lamp (E15/3) are switched off dimmed, when:

• no door is opened after a time set individually in the instrument cluster (A1) (0, 5, 10, 20 or 30 s)
• immediately when the ignition is switched back on again

Function sequence on ATA alarm triggering 

Function requirements:

• The vehicle is locked and the anti-theft alarm system (ATA) is activated.
• Dome lamp switch (N70s3) is set to position "Automatic actuation ON" or "Automatic actuation OFF".

The ATA triggers alarm and actuates the overhead control panel control unit (N70) with the message "ATA alarm". The overhead control panel control unit (N70) immediately triggers, without checking the automatic light switch daylight sensor (B32/1), the automatic dome lamp actuation and simultaneously switches on the front dome lamp (N70e1) integrated in the overhead control panel control unit (N70) and the dome lamp (E15/3e3) integrated in the rear dome lamp (E15/3) without dimming for the duration of the optical and acoustic ATA alarm.

Ambient lamp 

As of 24.4.04 an ambient lamp (A67e3) is installed, which is used for ambiance illumination. The ambient lamp (A67e3) is switched on with circuit 15R "ON" and switched off with circuit 15R "OFF". On vehicles with code (345a) rain sensor, except code (413) panoramic sliding roof (model 203.7) and except code (414a) electric glass tilting/sliding roof (model 203.0/2), the ambient lamp (A67e3) is switched on as soon as the Controller Area Network bus Class B (interior) (CAN-B) (1) is activated (e.g. unlocking).

The ambient lamp (A67e3) is switched off by the overhead control panel control unit (N70) 30 min after locking has been recognized and the Controller Area Network bus Class B (interior) (CAN-B) (1) has been deactivated.