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GF82.25-P-0010T Function of Special Taxi System



GF82.25-P-0010T Function Of Special Taxi System
- with CODE (450) Taxi version
- with CODE (934) Taxi emergency alarm unit







Function prerequisites:
^ No overvoltage or undervoltage

All functions of the special taxi system are monitored and controlled by the special vehicle multifunction control unit (SVMCU [MSS]) (N26/9).

The primary functions supported by this system are as follows (Taxi version Code 450):
^ power supply to service radio (A49)
^ electrical power supply to taximeter control unit (A67n1) or to conventional taximeter (A50)
^ data communications with the taximeter control unit (A67n1) via the serial communications interface RS485 or wiring with the conventional taximeter (A50)
^ electrical power supply to the interior socket (X58/1)
^ electrical power supply to glove compartment socket, which is actually a DIN socket situated beneath the glove compartment
^ control of the roof sign light (E14/4)
^ actuation of the left rear (E9/8) and right rear ashtray illumination (E9/9), as soon as at least the standing lamp is switched on

Switching the roof sign light on and off (E14/4)
The roof sign light (E14/4) is activated and deactivated using the instrument cluster (A1) with the keys on the multifunction steering wheel or the taximeter control unit (A67n1 ):
^ via the instrument cluster (A1):
using the buttons of the multifunction steering wheel call up SETTINGS menu,
scroll down to the submenu TAXI ROOF SIGN and switch the roof sign function on or off.

^ via the taximeter control unit (A67n1):
This function is only possible if the roof sign function is set via the instrument cluster (A1) to ON and the taximeter status is VACANT.
Activate and deactivate by pressing the right-side button on the taximeter and maintaining pressure until the roof sign light display lights up or goes out in the taximeter.

Special features of interior illumination.3
^ Opening a front door triggers the front dome lamp (N70e1) and the rear interior lamp (E15/3) , which are activated by the overhead control panel control unit (N70) .
^ Opening a rear door triggers only rear courtesy lamp the (E15/3).
^ When a vehicle door is open, the interior lamps switch off after two minutes (after five minutes on vehicles without taxi equipment).
^ In the CASHBOX status, the interior light is switched on automatically if the rain/light sensor (B38/2) indicates "dark" and the speed of the vehicle is ≤5 km/h.

Video system
A video system can also be installed to monitor the interior. The multifunction control unit for special-purpose vehicles (SVMCU [MSS]) (N26/9) is equipped with a door contact switch terminal for this feature. This makes it possible to use the door contact switches to control the video camera. The special vehicle multifunction control unit (SVMCU [MSS]) (N26/9) also incorporates a terminal that makes it possible to activate the interior lamps prior to switching on the video camera.

Programmable options
The Star Diagnosis can also be used to activate the following options:
^ Switching on/off the roof sign lamp (E14/4) if the CAN message "Open/close central locking" is received
^ program lower voltage limit for deactivating the roof sign light (E14/4) and the other electrical power supply terminals
^ allow deactivation of electrical power supply to taximeter ECU (A67n1)in response to low voltage yes/no?
^ automatic engagement of vehicle locks at speeds over 3 km/h
^ analysis of automatic seat occupancy monitor

Low voltage deactivation
If the voltage level in the vehicle electrical system falls below a defined level for longer than 5 s (the preset value is 11.5 volts), the system reacts by deactivating the power supply terminals from the special vehicle multifunction control unit (SVMCU [MSS]) (N26/9)(exception: taximeter).
The low-voltage deactivation function terminates automatically once the voltage level in the vehicle's on-board electrical system rises back beyond U=13 V.

Networking
The special vehicle multifunction control unit (SVMCU [MSS]) (N26/9) is linked with the interior CAN (see networking of components) for data communications (e.g., speed and wheel rotation rate signals).