Special Vehicle Multifunction Control Unit, Basic Function - GF82.25-P-9892B
Model all (CAR) with code Z90 (Multifunctional control unit for special functions) except code 965 (Taxi/rental car - electrical pre-installation)
Overview
This document contains information on:
- General
- Function requirements
- Function
- Reading in of sensors and signals
- Evaluation of input factors
- Output of signals
- Actuation of components
General
The special vehicle multifunction control unit (SVMCU) controls and monitors the additional functions for special-purpose vehicles and is connected to the vehicle's network architecture via the interior CAN.
Function requirements
The input factors are read in via the following connections:
- Direct line
- Interior CAN (CAN B1)
- Multifunction CAN (CAN K)
Direct line
The signals from the following components are read via direct lines: With code Z21 (Fire-extinguishing system) or code Z25 (Emergency fresh-air system):
- Fire extinguishing system and emergency fresh air system control unit
With code Z22 (Panic alarm system (PAS)):
- PAS [GAS] and special signal system control unit
- Emergency alarm system button
Interior CAN
The special vehicle multifunction control unit (SVMCU) reads in, among other things, the following signals via the interior CAN:
- Status of the central locking (CL)
- Circuit 15 status
- Engine running status
- Vehicle speed
- Battery voltage
Multifunction CAN
A connection to the fire extinguishing system control unit and emergency fresh-air system control unit is set up via the multifunction CAN.
Function
The input factors that have been read in are evaluated by the integrated microprocessor whereupon the corresponding signals and requests are output and components are actuated.
Signals, information and requests are output via the following connections:
- Direct line
- Interior CAN (CAN B1)
- Multifunction CAN (CAN K)
Direct line
The special vehicle multifunction control unit (SVMCU) sends signals to the following component via a direct line:
With code Z22 (Panic alarm system (PAS)):
- PAS [GAS] and special signal system control unit
Interior CAN
The special vehicle multifunction control unit (SVMCU) sends, among other things, the following signals via the interior CAN:
- Request for switching on "recirculated air"
- Request for alarm light functions (with code Z22 (Panic alarm system (PAS)))
- Request for alarm flashing (with code Z22 (Panic alarm system (PAS)))
- Request for closing central locking system (with code Z22 (Panic alarm system (PAS)))
- Request for audio mute (with code Z22 (Panic alarm system (PAS)))
- Request for warning messages for instrument cluster The functions that use these signals are described in the individual function descriptions (see block diagram or function schematic).
Multifunction CAN
The special vehicle multifunction control unit (SVMCU) sends, among other things, the following signals via the multifunction CAN:
- Circuit status
- Wheel speed
- Diagnosis requests
The functions that result from this are described in the respective function descriptions (see function schematic).
Actuation of components
On vehicles with CODE Z61 (Auxiliary battery for emergency start), the special vehicle multifunction control unit (SVMCU) actuates the emergency start system relay (high current) (K53/12) directly.
| Component descriptions | |||
|---|---|---|---|
| Multifunction control unit, component description | Model 223 with code Z90 (Multifunctional control unit for special functions) except code 965 (Taxi/rental car - electrical pre-installation) |
GF82.25-P-9893A |