Navigation, Function - GF82.61-P-2003KJ
MODEL 453.0/3/4
with CODE 535 (smart Media system)
Shown on vehicle with engine 281 and code 410 (5-speed manual transmission)
In vehicles with engine 281 and code 429 (twinamic) and in model 453.091/391/491, the status "reverse gear engaged" is read in by the electronic selector lever module control unit (N15/5) and made available to the center SAM control unit via a direct line. The center SAM control unit then places this information on the interior CAN. The audio gateway control unit makes this information available to the smart radio multimedia navigator via the telematics CAN.
Function requirements for Secure Digital (SD) card navigation, general
The following abbreviations are used in the following text: Global Positioning System (GPS) and Universal Serial Bus (USB).
- Circuit 30g ON
- Transport mode not active
- Authorized SD card is inserted into SD card slot of multimedia connection unit
- Signals available from at least three GPS satellites
- Smart radio multimedia navigator is switched on
SD card navigation, general
During SD card navigation, the smart radio multimedia navigator is supported by the following vehicle components:
- Activation of the menu via the touchscreen of the smart radio multimedia navigator
- Map data of the SD card via the multimedia connection unit
- GPS signals from the GPS antenna
- Operation via the right multifunction steering wheel button group
- Audio output via the in-door speakers
- Picture output and map display on the smart radio multimedia navigator display; view and menu display generated by the smart radio multimedia navigator using the SD map data provided by the multimedia connection unit
- Real-time traffic data from the telematics services communications module (N112/2) or comparable radio traffic messages via the FM radio tuners integrated into the radio
- Updates of map data and navigation software via SD card on an Internet-capable PC
Function sequence for SD card navigation
The control signals from the multimedia operating unit are read in by the smart radio multimedia navigator via interior CAN:
- Interior CAN
The SD card and the smart radio multimedia navigator exchange the map data via the multimedia connection unit and a USB connection.
The smart radio multimedia navigator receives the GPS signals from the GPS antenna via a direct line.
Since GPS operates in the gigahertz range (microwaves) and the signals are weak, the following events may lead to reception interference: Atmospheric interferences (e.g. bad weather, water vapor, fog), multi-path reception due to reflections of the signals (e.g. at building walls) or signal shadowing (e.g. in built-up areas, in tunnels, due to tall buildings or trees)
In the event of a failure of the GPS signals, the smart radio multimedia navigator reverts back to the basic position finding. For basic position finding, the smart radio multimedia navigator evaluates the data of the integrated 2D gyro sensor as well as the wheel speed signals it receives from the electronic stability program control unit via interior CAN. Position finding errors in position finding, rolling backwards with "circuit 15 OFF" (ignition switched off) or transport of the vehicle falsify the basic position finding. In both instances, the deviation is automatically corrected by the navigation processor integrated into the smart radio multimedia navigator when it receives GPS data.
The control signals of the right multifunction steering wheel button group are transmitted to the smart radio multimedia navigator head unit via the following route:
- Steering wheel clock spring contact
- Audio gateway control unit
- Interior CAN
- Smart radio multimedia navigator
The smart radio multimedia navigator forwards the voice output to the radio via telematics CAN. The radio amplifies the signals and forwards them to the in-door speakers.
More detailed information on the speaker system is available in the "Speaker output function" document.
The traffic messages from the integrated FM radio tuners are transferred within the smart radio multimedia navigator.
Further information on the telematics services communications module (N112/2) can be found in the document "Telematics services communications module, component description".
Updates on the SD card takes are downloaded externally on an Internet-capable PC; this is described in the operator's manual.
| Electrical function schematic for navigation system function | PE82.61-P-2056-97BBA | ||
| Overview of system components, telematics | GF82.85-P-9999KJ |