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GF82.25-P-0001T Special Signal System For Government and Emergency Vehicles, Function



GF82.25-P-0001T Special Signal System For Government And Emergency Vehicles, Function
- with CODE (970) police emergency vehicles














The special signal system of government and emergency vehicles is used to control the optical and acoustic signals in the event of an operation during which the priority vehicle warning light is used.

All functions are controlled by the special vehicle multifunction control unit (MSS) (N26/9) in connection with the central gateway control unit (N93).

Various options can be programmed in the special vehicle multifunction control unit (MSS) (N26/9):
^ Alarm options
^ Alarm options for the panic alarm system (GAS) function
^ Alarm options for 2nd battery function
^ Rpm value for 2nd battery function
^ Battery indicator
^ Undervoltage value
^ Light version
^ Circuit status for signal sequence and two-way radio
^ Rear flash lamp
^ Seat contact function
^ Starter lock function
^ Brightness phases for signal sequence

In the event of an operation during which the priority vehicle warning light is used, the special vehicle multifunction control unit (MSS) (N26/9) controls the following lamps depending on the programming:
- Priority vehicle warning light
- High beam or fog lamp
- Low beam
- Flash lamp in the trunk lid

Various special signals can be requested with the push of a button via the special signal operating unit (audio and light) (A48):
- Flashing light without special signal
- Flashing light with special signal and horn contact
- Flashing light with constant special signal

Blue light recognition
The special vehicle multifunction control unit (SVMCU [MSS]) (N26/9) recognizes through voltage of a control line from the special signal operating unit (audio and light) (A48), whether the priority vehicle warning light is switched on. With the government vehicle and disguised emergency vehicles (without special roof light bar) the special vehicle multifunction control unit (MSS) (N26/9) actuates the priority vehicle warning light.

The priority vehicle warning light is integrated in emergency vehicles with special roof light bar and is directly actuated by the special signal operating unit (audio and light) (A48). (see description by the manufacturer.)

Triggering the special signal via horn contact
If the priority vehicle warning light is switched on, the actuation of the fanfare horns buttons (S110s5, S111s5) is transmitted via the CAN interior to the special vehicle multifunction control unit (SVMCU [MSS]) (N26/9). As long as the fanfare horns buttons (S110s5, S111s5) are operated, the special vehicle multifunction control unit (MSS) (N26/9) switches a discrete line to the special signal operating unit (audio and light) (A48) to ground. The special signal system carries out a complete special signal cycle. If the line is still connected to ground after the cycle is completed, another special signal cycle is carried out.

Output of the special signals
The output of the optical and acoustic special signals depends on the vehicle version:
^ open version: via special roof light bar (Hella RTK-6 optical and acoustic signal system),
^ disguised version: via rotating beacon at the roof, plug-in type (Splithoff lamp) and outside speakers in front,
^ fully disguised version: via rotating beacon (Kojak lamp) and outside speakers in front.

Two-way radio system
The two-way radio system is switched on and off with the main radio switch (in the center console, on the right next to the gearshift lever). The mode is indicated by an indicator lamp. The two-way radio system consists of one or two linked two-way radio systems. Depending on the equipment, the transmitter and receiver unit is either located on the implement carrier in the luggage compartment, or it forms a unit with the operating module (in the glove compartment).

The connections of the two-way radio system are equipped with a undervoltage protection. If the battery voltage drops below 11.2 Volts, the two-way radio system is automatically switched off in order to protect the battery.

Low voltage deactivation
If undervoltage is recognized, the central gateway control unit (N93) sends a signal via the CAN interior to the special vehicle multifunction control unit (SVMCU [MSS]) (N26/9).
The signaling process takes place in two levels of priority. The special vehicle multifunction control unit (SVMCU [MSS]) (N26/9) immediately switches off the appropriate consumers when it receives the priority levels.