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Two-way radio integration function - GF82.25-P-2014CE

MODEL 204.0 /2 with CODE (965) Electrical preinstallation for rental vehicles with CODE (941) Preinstallation for radio data transmission as of model year 2009 /YoM 08 

Function requirements, general 

IMPORTANT The electronic ignition lock control unit (N73) sends the status of circuit 15 via interior CAN (CAN B) to the special-purpose vehicle multifunction control unit (N26/9).

Two-way radio integration, general The two-way radio integration is a preinstallation for the operation of the voice radio transmission and radio data transmission that allows the driver to establish communication, e.g. with the taxi main office, via the radio data transmission two-way radio (A49/5) (accessories).

The two-way radio integration is comprised of the following partial functions:

Additional function requirements for switching on the radio data transmission two-way radio 

Function sequence for switching on the radio data transmission two-way radio 

The radio data transmission two-way radio is a preinstallation for the two-way radio that is located in the spare wheel well in the trunk.

Using the left multifunction steering wheel button group (S110) and right multifunction steering wheel button group (S111), a radio connection, e.g. with the taxi main office, can be established via the radio data transmission two-way radio. The communication via two-way radio is cyclically sent to an output (two-way radio source) of the multifunction control unit. If the cyclical two-way radio source is interrupted, this can be activated again following t = 5 s.

The multifunction control unit sends status information via interior CAN and this is shown in the travel distance display (A1p7) (without code (442) Comfort multifunction steering wheel) or in the multifunction display (A1p13) (with code (442) Comfort multifunction steering wheel) of the instrument cluster. Pressing the multifunction steering wheel button groups signals the multifunction control unit that a two-way radio connection should be activated.

The signals of the multifunction steering wheel button groups are read in by the steering wheel electronics (N135) and transmitted via the steering LIN (LIN E1) to the steering column tube module control unit (N80).

The steering column tube module control unit routes the signals via chassis CAN (CAN E), front SAM control unit with fuse and relay module (N10/1) and interior CAN to the multifunction control unit.

Following this, the multifunction control unit activates the radio data transmission two-way radio.

Alternatively, the radio data transmission two-way radio can also be activated upon unlocking the central locking (CL [ZV]) if taxi mode was not switched off beforehand.

The FM, AM and CL [ZV] antenna amplifier (A2/18) (model 204.0) or rear window antenna amplifier 1 (A2/71) (model 204.2) receives the radio signals of the transmitter key (A8/1) and forwards them via the rear SAM control unit with fuse and relay module (N10/2) to the electronic ignition lock control unit. The electronic ignition lock control unit sends the status "CL [ZV] unlocked" via interior CAN to the multifunction control unit, which then activates the radio data transmission two-way radio.

Function sequence for switching off the radio data transmission two-way radio 

The radio data transmission two-way radio can be switched off manually or automatically.

This is performed manually via the multifunction steering wheel button groups. To do so, the "Two-way radio" menu must be selected in the instrument cluster. After switching off the radio data transmission two-way radio, the message "Charge two-way radio with +" appears in the travel distance display or in the multifunction display.

In addition, three beeps sound that are output via the warning buzzer (A1h1).

IMPORTANT If the radio data transmission two-way radio was switched off via the right multifunction steering wheel button group, this cannot be activated by unlocking the CL [ZV] or switching on circuit 15 C. The radio data transmission two-way radio can only be activated by pressing the multifunction steering wheel button groups or by triggering an emergency alarm with radio help call.

If the CL [ZV] is locked with the transmitter key, the multifunction control unit automatically switches off the radio data transmission two-way radio after the expiration of a programmable time (standard t = 30 m).

The FM, AM and CL [ZV] antenna amplifier or the rear window antenna amplifier 1 receives the radio signals of the transmitter key and forwards them via rear SAM control unit to the electronic ignition lock control unit.

The electronic ignition lock control unit then sends the status "CL [ZV] locked" via interior CAN to the multifunction control unit.

Function sequence for fault detection 

If the radio data transmission two-way radio does not answer within the permissible time, e.g. due to an internal overload of 50 consecutive status queries, the radio data transmission two-way radio is disconnected from the power supply for approx. t = 5 s. The radio data transmission two-way radio is returned to a functioning state by means of this "power-off reset".

The multifunction control unit ends any dialogs with instrument cluster that are still open. A "power-off reset" is signaled by the warning buzzer in the instrument cluster by five beeps. After approx. t = 5 s, the radio data transmission two-way radio is supplied with voltage again and receives status queries.

REFER TO SYSTEM WIRING DIAGRAMS Electrical function schematic for two-way radio integration   PE82.25-P-2063-97FAA
  Component description for instrument cluster A1 GF54.30-P-6000CE
  Component description for front SAM control unit with fuse and relay module N10/1 GF54.21-P-6070CE
  Component description for rear SAM control unit with fuse and relay module N10/2 GF54.21-P-6030CE
  Special vehicle multifunction control unit (SVMCU [MSS]), component description N26/9 GF54.21-P-4010CE
  Component description for the electronic ignition lock control unit N73 GF80.57-P-6001CE
  Component description for steering column tube module control unit N80 GF54.21-P-6051CE