Special vehicles multifunction control module task - GF82.25-P-4102-02PP

The multifunction control unit for special-purpose vehicles (MSS) (N26/9)  monitors and controls special functions in special duty vehicles.

Aside from discharging internal functions, the MSS also serves as the interface linking the interior bus (CAN-B) with those ECUs that are not equipped with a separate individual CAN connection.

The control unit can distinguish between two basic status conditions

• Taxi
• Special-purpose vehicles
  • Government vehicles
  • Police and emergency vehicles
  • A panic-mode is available for private vehicles on customer request.

Depending on the codes entered in the control unit and the equipment level the MSS can perform the following:

• voltage supply to service radio (A49)
• voltage supply to taximeter ECU (A67n1) or to conventional taximeter (A50)
• maintain bilateral data communications with the taximeter ECU (A67n1) via the serial communications port (RS485) or with the conventional taximeter (A50) via four wires.
• voltage supply to the interior power socket (X58/1)
• voltage supply to the glove compartment socket (X29/6)
• control of the taxi emergency alarm system
• control of the roof sign light (E14/4)
• control of the rear ashtray lamp (E9/10)
• control of some functions of the special signal system
• control of the panic-mode alarm function (private vehicles)
• control and regulation of the windshield defroster (Special-duty vehicles)

Networking 

The control unit is linked to the interior CAN for data communications.

Entering control unit codes  Codes are entered in the ECU using the Star Diagnosis tool connected to the control unit EZS (N73) 

Exceptions: The codes for windshield defroster function and the functions for police vehicles disguised as taxis are entered directly into the MSS.

Taxis 

The different emergency call functions available for taxis are activated and deactivated in MSS using the Star Diagnosis tool.

The alarm system's operational response depends on the version code stored in the MSS. The reaction can be a total alarm or a silent alarm; the latter is not perceptible within the vehicle.

These alarms can also be supplemented by a taxi SOS call.

An officially prescribed procedure is available for evaluating operation of the taxi SOS call function!