GF82.70-P-3114-04T Telecommunications Control Unit, Function

GF82.70-P-3114-04T Telecommunications Control Unit, Function

The telecommunications control unit (N112) can be operated using the telephone handset (A34) or the hands-free system. It is available as special equipment in 2 versions:
^ In vehicles with code (381) MB telephone "Standard" in console on right side of dome.
^ In vehicles with code (383) MB telephone "Standard" in console on right side of dome with integrated TELE AID emergency call system, hands-free system and antenna

The telecommunications control unit (N112) can be activated as follows:
^ Wake-up line (triggered by operating unit)
^ Switch group SOS/ATA (S93/3), MB-Info and telediagnosis button group (S93/6)
^ Incoming call
^ Diagnosis inquiry from central gateway (N93)

The communications system is fitted and configured at the factory. All the configurations have, regardless of the communications standard, identical wiring harnesses, plugs and housings with identical dimensions. The modular communications platform contains the main circuit (Mainboard).
The Mainboard contains the communications platform, the ROM and RAM memory, the interface to the MOST, and the discrete vehicle interfaces. The telecommunications control unit (N112) is designed such that Mainboard components can be removed or replaced.
The following components can be upgraded individually:
^ RAM, ROM memories
^ CPU
^ Wireless communications systems
^ GPS computer

Authorization
In order to start using the respective telephone system with the relevant service provider, authorization is required, i.e. personal and vehicle-related information has to be entered into the telecommunications control unit (N112) that has been coded in the factory and forwarded to the authorization center (Customer Assistant Center (CAC)).
A service is authorized when it is technically useable.

Cellular service provider
Customers with a SIM card (Subscriber Identification Module) have their own contract with the mobile radio provider. He/she pays a monthly fee and the accrued call costs. Voice calls can be made using this SIM card (Subscriber Identification Module). If this SIM card (Subscriber Identification Module) is installed in the telecommunications control unit (N112), telematics services can also be used with this SIM card (Subscriber Identification Module).

TT card (Traffic Telematics Card)
The TT card (Traffic Telematics Card) is a fixed constituent of the telecommunications control unit (N112) and the vehicle. The contract for this TT card (Traffic Telematics Card) is between DaimlerChrysler AG and the mobile radio provider. The customer only has access to on-board telematics services using this TT card (Traffic Telematics Card). To make voice calls that are not directly related to on-board services the customer requires an additional SIM card (Subscriber Identification Module) as described below.

Emergency call function
The security software for vehicles with code (855) TELE AID runs on the communications platform. Therefore, an independent GPS module is needed, which supplies the system with the data for position finding. The GPS module contains a GPS receiver with gyro sensor. An external satellite antenna is needed in order to receive satellite information.

The GPS antenna (A2/49a2) (model 211.0) or the GPS antenna (A2/23) (model 211.2) is used in combination with the navigation system via the GPS antenna splitter (A2/5).

Via the restraint systems control unit (N2/7), the telecommunications control unit (N112) receives the crash signal, whereupon an emergency call is initiated. The GPS module supplies the position data. The emergency call is subsequently relayed directly via the telephone transmitter to the emergency call center.

Hands-free system microphone group (A67b1)/speaker
The telecommunications control unit (N112) takes control of the hands-free system microphone group (A67b1) by applying a direct voltage of 8 V at the microphone input. The analog audio signal is routed by the telecommunications control unit (N112) via a relay. The voice input takes place via the hands-free system microphone group (A67b1) in the inside rearview mirror unit (A67). The voice output takes place via the central speaker.

The emergency call and telediagnosis functions in vehicles with code (855) TELE AID need system-independent voice input and output in case of an emergency. In an emergency, the voice output takes place via 2 separate speakers. The connection to the handsfree system microphone group (A67b1) and the speakers has diagnosis capability.

Telephone operation
The telephone handset (A34) or hands-free system is needed to operate the telephone. Activation and operation can take place via the radio control panel and navigation unit (A2/56) in vehicles with code (525) MB Audio 50 APS radio, or the COMAND operating, display and control unit (A40/3) in vehicles with code (527) navigation module for COMAND, the telephone handset (A34) or the voice control system (VCS).
The transmit/receive unit in the telecommunications control unit (N112) transfers the data (caller voice, control data, telephone numbers) to the telephone antenna (A2/49 a1) in model 211.0 or the telephone antenna (A2/22) in model 211.2.

Vice versa, the incoming oscillations are converted into digital signals, again converted into optical pulses (MOST) and transmitted to the corresponding control units.

Internet
Internet messages, as with telephone calls, are transmitted via the transmitting and receiving circuits of the cellular radio system.

Messages received by the internal transmit/receive unit are prepared in the Internet browser (computer) that is also integrated in the telecommunications control unit (N112) and sent to the central computer of the radio control panel and navigation unit (A2/56) in vehicles with code (525) MB Audio 50 APS radio, or the COMAND operating, display and control unit (A40/3) in vehicles with code (527) navigation module for COMAND. Both computers are continuously communicating with one another.