Navigation Mode, Function - GF82.85-P-2012RF
Model 205 up to model year 2019 with code 531 (COMAND® APS)
Model 253 (except 253.99) up to model year 2020 with code 531 (COMAND® APS)
Shown on model 205.0/2/3, 253 as of 01.06.2016
Shown on model 205.0/2/3, 253 up to 31.05.2016
Shown: model 205.4
Function requirements for navigation mode in general
- Status circuit 30g ON
- Transport mode not active
General navigation mode
The navigation module is integrated in the head unit. The navigation system includes the following functionalities:
- Position finding
- Destination entry
- Route calculation
- Display of navigation maps
- Intersection zoom
- Visual driving instructions in form of pictograms
- Acoustic driving instructions
The location and direction of movement of the vehicle are continuously determined with the aid of the navigation system. After entering or selecting a destination location, route calculation starts.
There is a choice of a range of options for route calculation according to the national version, e.g.:
- "Fast route"
- "Dynamic route"
- "Eco Route"
- "Short route"
- Avoid options (e.g. "Avoid area", "Avoid tunnel", "Avoid ferries", "Avoid toll sticker roads")
If observance of the options is not possible, then the options set are ignored for the sections in question and a message is displayed and signaled audibly. The set options can be displayed and changed at any time. Once calculated, the route is displayed using arrow pictograms on the Audio/COMAND® display and this information is also issued as an acoustic notification: "The route is being calculated". If the vehicle deviates from the route, the new route is re-calculated. If the recalculated values are plausible for the navigation system, then the modified route is displayed.
Dynamic route guidance (with "Dynamic route", "Dynamic route with confirmation" or "Eco route"): An alternative route is offered under dynamic route guidance, in the event of a sufficiently long traffic jam or road closure on the calculated route.
The navigation system also has lists and map data for points of interest (e.g. restaurants, filling stations, parking lots, shopping centers), which can be selected as the destination or for a stopover.
Model 205 up to model year 2019 with code 531 (COMAND® APS) except code 498 (Japanese version)
Model 253 (except 253.99) up to model year 2020 with code 531 (COMAND® APS) except code 498 (Japanese version)
Routes can be transmitted from the Internet via the Mercedes-Benz Application Gateway to the vehicle and imported into the navigation system.
Destination entries or points of interest can be made available to the navigation module of the head unit by the Service Center.
The navigation system can be operated with the following components:
- Upper control panel control unit
The upper control panel control unit transmits the operation signals via the LCP-LIN, Audio/COMAND® control panel and telematics CAN to the head unit.
- Audio/COMAND® control panel
The Audio/COMAND® control panel sends the control signals via telematics CAN to the head unit.
- Touchpad (up to 31.05.2015 with code 531 (COMAND® APS), as of 01.06.2015 with code 448 (Touchpad), with code 498 (Japan version) or code 494 (USA version))
The touchpad sends the operation signals over the telematics CAN to the head unit.
- Left multifunction steering wheel button group and right multifunction steering wheel button group
The steering wheel electronics reads the control signals of the left multifunction steering wheel button group and right multifunction steering wheel button group directly. The steering column tube module control unit reads them via the steering LIN and transmits them to the instrument cluster via chassis FlexRay, the electronic ignition lock control unit and user interface CAN. The instrument cluster transmits the operation signals from the left multifunction steering wheel button group and right multifunction steering wheel button group to the head unit via the user interface CAN.
- Voice control system (VCS [SBS])
When operating via the VCS, the voice input takes place using the hands-free system microphone. The words spoken are converted into an electric signal and routed to the head unit.
Additional name lists are provided in the navigation system for the VCS of the navigation system, particularly destination entry, e.g. for the following information: place names for selected towns/cities on the data storage medium, street names for all cities, city centers and points of interest (POIs).
The navigation mode function includes the following subfunctions:
- GPS position finding
- Basic position finding
- Route calculation
- Destination-oriented navigation
- Dynamic route guidance (except for code 494 (USA version), except for code 498 (Japan version), except for code B54 (Live Traffic Information) and except for code 367 (Live Traffic Information))
- Vehicle Information and Communication System (VICS) over the FM multiplexer (with code 498 (Japan version))
- Dynamic route guidance with VICS (with code 498 (Japan version))
- Dynamic route guidance with Real Time Traffic Data (RTTD) (with code 536 (SIRIUS satellite radio))
- Dynamic route guidance with real-time traffic data via the telematics services communications module (with code B54 (Live Traffic Information)) or via the HERMES control unit (with code 367 (Live Traffic Information))
- Map function
- Extended navigation functions
The navigation system uses a special interface to provide data that is used by other systems in the vehicle. The head unit transmits the data via the user interface CAN.
GPS position finding
The GPS is a satellite-based position finding system, which is available on a global basis. GPS position finding is irretrievable after vehicle transport (e.g. by train or ferry or after towing). Recalculating the GPS position (after satellite reception has been interrupted) can take several minutes (up to 5 minutes during initial commissioning). The accuracy of the position finding and the actual calculation are essentially based on the measurement of the run times of the signals sent synchronously by the various satellites. A vital precondition is the synchronicity of the clocks in the satellites and in the receiver. To ensure synchronicity, the receiver is equipped with an automatic time correction that is possible thanks to the satellite signals.
The GPS receiver in the head unit receives the GPS signals from the GPS antenna. The head unit calculates the current position of the vehicle from the GPS signals. The direction of travel is determined with the aid of the sequence of locations calculated with the GPS system.
Because GPS works in the gigahertz (GHz) range (microwaves) and the signals are weak, the following events may lead to reception interference: Atmospheric interferences (e.g. bad weather, water vapor, fog), multiple 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 higher buildings or trees).
Basic position finding
If no GPS signal is received during route guidance, navigation is still possible with basic position finding. A defect, e.g. in the GPS antenna is therefore not immediately perceptible. Basic position finding runs parallel to GPS position finding.
For basic position finding the head unit requires the following information:
- Wheel speed and wheel rotation direction (forwards or backwards) from the Electronic Stability Program control unit
The ESP® control unit transmits information on the wheel speeds and the wheel rotation direction to the head unit via the suspension FlexRay, electronic ignition lock control unit and user interface CAN.
- Angular velocity of the rotation from the gyro sensor in the head unit
- Ramp detection via the 3D acceleration sensor in the head unit
The head unit calculates the current vehicle position (longitude and latitude) around once per second.
Location faults during position finding, rolling backward with circuit 15 OFF or vehicle transportation falsify basic position finding. The deviation is automatically corrected by the navigation processor integrated in the head unit when GPS data is received.
The calibration following a tire replacement is performed automatically.
Because of the tire abrasion, a constant recalibration of the tire circumference is required. Recalibration is carried out automatically and uses the difference between the calculated and actually traveled distance between two turning points that has been determined using map-based position finding.
Route calculation
Route calculation is accomplished using the options set to the best possible extent. If observance of the options is not possible, they are ignored for the stretches in question. Visual and acoustic signals are also output. The set options can be changed at any time. When the route is being calculated, the message "Calculating route" is output. Following calculation, the route is displayed by arrow pictograms on the Audio/COMAND® display. If the vehicle is no longer traveling along the precalculated route, the route is recalculated. If the recalculated values are plausible for the navigation system, then the modified route is displayed.
Destination-oriented navigation
The integrated navigation processor continuously compares the route calculation data with the position finding data and uses the data to deduce measures for further route guidance. The route guidance is carried out by outputting visual and acoustic information and is divided up into the following areas:
- Map route guidance
- Route guidance through driving lane recommendations
- Route guidance by means of voice output
Map route guidance
Route guidance via a map is shown on the Audio/COMAND® display. The head unit transmits a switch-on request to the Audio/COMAND® display via the telematics CAN. At the same time, the head unit generates the signals for visualizing route guidance (map navigation) and transmits them to the Audio/COMAND® display via the LVDS line.
Route guidance through driving lane recommendations
For certain turnoff situations on multiple-lane departures (e.g. freeway intersection), driving lane recommendations are shown in the bottom line. When a turnoff recommendation is given, the distance to the turnoff point is also displayed using a bar graph. The lanes have arrows assigned to them, which indicate on which lane the destination can be reached or the best way to reach it.
With day design, the following colors are used on the Audio/COMAND® display:
White: the best or recommended lane
Light gray: the lane is correct, but a lane change will soon be required.
Dark gray: this lane will not take you to the destination.
Route guidance by means of voice output
Route guidance by means of voice output is an assistance function that assists the driver without distracting him from the traffic. Voice is output with the selected system language. The route guidance of the navigation system is supported by voice outputs with the following information:
- Directional instructions
- Name of the next road to turn into.
Further voice messages take place, e.g. at the start of route calculation, when an intermediate destination has been reached, or when the destination has been reached.
During dynamic route guidance, additional voice messages are issued due to traffic messages affecting the route. In some cases, special information is also issued via voice output in certain circumstances, e.g.:
- Destination lies in area where driving is only possible to a limited extent
- Route via ferry
The navigation processor of the head unit links word segments to form complete instructions or information during voice output.
In vehicles without CODE 810 (Sound system), the voice output is relayed to the speaker system by the head unit.
In vehicles with CODE 810 (Sound system), the head unit transmits the voice output via the MOST to the sound system amplifier control unit. The sound system amplifier control unit amplifies the signals and forwards them to the speaker system.
The volume of the voice output can be adjusted during voice input via the volume control button in the lower control panel on the right, the volume adjustment button in the lower control panel on the left or via the multifunction steering wheel button group on the right.
The right lower control panel transmits the operation signals of the volume control button and the left lower control panel transmits the operation signals of the volume adjustment button to the head unit via the LCP-LIN, Audio/COMAND® control panel and telematics CAN.
The steering wheel electronics reads the control signals from the left multifunction steering wheel button group and right multifunction steering wheel button group directly. The steering column tube module control unit reads them via the steering LIN and transmits them to the instrument cluster via chassis FlexRay, the electronic ignition lock control unit and user interface CAN. The instrument cluster transmits the control signals from the left multifunction steering wheel button group and right multifunction steering wheel button group to the head unit via the user interface CAN.
Dynamic route guidance (except for code 494 (USA version), except for code 498 (Japan version), except for code B54 (Live Traffic Information) and except for code 367 (Live Traffic Information))
Dynamic route guidance is performed in "Dynamic route", "Dynamic route with confirmation" or "Eco route" mode (except code 498 (Japan version)). During dynamic route guidance the current traffic situation is taken into consideration when appropriate traffic data is received. The traffic data recorder decodes the traffic information and forwards it internally to the navigation processor upon request. The navigation processor makes the decision whether the route should be changed. During dynamic routing with confirmation, the user is notified of the effects of the route change on the travel distance and driving time. The route is only changed with the user's agreement.
If necessary, a message that the route should be changed is output via the speaker system.
The incoming information about the traffic situation can be received by the Radio Data System/Traffic Message Channel (RDS/TMC) function via FM radio or digital radio (DAB) (with code 537 (Digital radio (DAB))) if an appropriate station has been selected.
Model 205 as of model year 2017 up to model year 2019 with code 367 (Live Traffic Information)
with code 531 (COMAND® APS)
Dynamic route guidance via RDS/TMC occurs if no real-time traffic data is received (e.g. no valid subscription or the vehicle is not within the geographical area for which the traffic data service is offered).
For model 205.0/3, the head unit receives the traffic information via the rear window antenna, antenna amplifier FM1, AM, ZV and KEYLESS-GO or the antenna amplifier FM 2 and DAB Band III.
For model 205.4, the head unit receives the traffic information via the windshield antenna, antenna amplifier FM1, AM, ZV and KEYLESS-GO or the antenna amplifier FM 2, DAB and TV 1.
For model 205.2, 253, the head unit receives the traffic information via the rear spoiler antenna and the antenna amplifier FM1, AM, ZV and KEYLESS-GO.
The FM receiver in the head unit forwards the traffic messages to the traffic data recorder in the head unit.
With model 205.0/3 with code 537 (Digital radio (DAB)), the tuner unit receives the DAB Band III signals via the rear window antenna and antenna amplifier FM 2 and DAB Band III/antenna amplifier TV 1 and DAB Band III.
With model 205.4 with code 537 (Digital radio (DAB)), the tuner unit receives the DAB Band III signals via the windshield antenna and antenna amplifier TV 2 and DAB Band III and the antenna splitter TV and DAB or the antenna amplifier and FM 2, DAB and TV 1.
With model 205.2, 253 with code 537 (Digital radio (DAB)), the tuner unit receives the DAB Band III signals via the rear window antenna and antenna amplifier FM 2, DAB and TV 1 (first DAB BAND III signal) and antenna amplifier TV 1 and DAB Band III (second DAB BAND III signal).
The tuner unit forwards the traffic messages in the digital radio to the head unit via the MOST. The traffic messages are stored in the traffic data recorder of the head unit and prepared for the integrated navigation processor.
Vehicle Information and Communication System (VICS) over the FM multiplexer (with code 498 (Japan version))
The driver is provided with vital information by the VICS on the current traffic situation. Traffic impairments and traffic jams are shown on the map, however they are not incorporated into the dynamic route guidance. The VICS messages are transmitted as FM radio signals. The head unit receives the FM-1 signals via the rear window antenna (model 205.0/3) or the rear spoiler antenna (model 205.2, 253) and the antenna amplifier FM 1, AM, ZV and KEYLESS-GO.
The head unit receives the FM-2 signals via the rear window antenna and antenna amplifier FM 2 and DAB Band III (model 205.0) or antenna amplifier FM 2, DAB and TV 1 (model 205.2, 253).
The VICS information is processed in the FM multiplexer integrated in the head unit. The head unit then transmits the corresponding data for displaying the information to the Audio/COMAND® display via the LVDS line.
Dynamic route guidance with VICS (with code 498 (Japan version))
The Vehicle Information and Communication System (VICS) control unit and the Dedicated Short-Range Communications control unit are required for dynamic route guidance. The Vehicle Information and Communication System (VICS) control unit contains both the receiver and the antenna. The antenna communicates with the VICS beacons (transmitter masts) installed at the roadside which transmit microwave signals within a 2.5 gigahertz reception range or infrared signals. The received signals are transmitted directly to the head unit and decoded. The Dedicated Short-Range Communications control unit receives VICS signals in the 5.8 gigahertz reception range via the DSRC antenna and forwards them to the head unit. The traffic messages are stored in the traffic data recorder of the head unit, decrypted and forwarded to the navigation processor on request.
Dynamic route guidance with Real Time Traffic Data (RTTD) (with code 536 (SIRIUS satellite radio))
RTTD are real-time traffic data that is transmitted through the "Sirius" satellite radio provider and the reception and processing of the data is made possible by the tuner unit. The real time traffic data contain accident and traffic jam messages as well as traffic flow information. The real-time traffic data is available around the major cities in the USA, and is transmitted every 5 minutes. The tuner unit receives the real-time traffic data via direct line from the SDARS antenna and makes it available to the navigation system of the head unit via the MOST. The head unit uses the data to compute alternative routes and shows it via an LVDS line on the audio/COMAND® display.
Additional function requirements for dynamic route guidance with real-time traffic data via the telematics services communications module (with code B54 (Live Traffic Information)) or via the HERMES control unit (with code 367 (Live Traffic Information))
- Subscription for real-time traffic data
- The vehicle is located within the geographical area that is covered by the traffic data service.
Dynamic route guidance with real-time traffic data via the telematics services communications module (with code B54 (Live Traffic Information)) or via the HERMES control unit (with code 367 (Live Traffic Information))
In vehicles with code B54 (Live Traffic Information), the telematics services communications module receives the real-time traffic data via the communications module/stationary heater antenna and communications module/stationary heater antenna splitter. In vehicles with code 367 (Live Traffic Information) the HERMES control unit receives the real-time traffic data from the service provider via the emergency call system antenna.
The telematics services communications module or the HERMES control unit transmits the real-time traffic data via a direct line (Universal Serial Bus (USB)) to the head unit, where it can be used by the integrated navigation processor.
The telematics services communications module or the HERMES control unit receives position data from the head unit cyclically via a direct line (USB). In vehicles with code B54 (Live Traffic Information) the telematics services communications module transmits the position data to the service provider via the communications module/stationary heater antenna. In vehicles with code 367 (Live Traffic Information) the HERMES control unit transmits the position data to the service provider via the emergency call system antenna. In this way, the telematics services communications module or the HERMES control unit contributes to collecting the traffic information, from which the dynamic route guidance then benefits in turn.
Map function
The map display is always controlled by the head unit. The following display functions are supported:
- Route guidance map
- Positioning map
- Route map
- Scrollable map
- Destination entry map
Extended navigation functions
The navigation system is extended with regard to convenience, customization and tourist information by the following functions:
- Integration of electronic travel guide, destination build-up and downloading of routes via a Secure Digital (SD) card and the SD card slot of the multimedia connection unit
- Special search engine that also makes fuzzy destination entries possible (e.g. part of destination town, street or points of interest).
- "Route flight" (provides a visual overview of the planned route from a bird's eye view)
- "Drive Show" (sequence of pictures, which show the current position, route, traffic information along the route, vicinity of the destination and the altitude course of the route currently being navigated)
- "Compass" (display of a compass screen, which also contains the geo-coordinates for the current position and the current altitude)
- Possibility to access the Mercedes-Benz "Travel guide" (accessory) via the SD card reader in the multimedia connection unit
Data communication between the head unit and the SD card takes place via the USB connection between the head unit and the multimedia connection unit.
The extended navigation mode functions are converted internally in the head unit and - where applicable - shown over the LVDS line on the Audio/COMAND® display.
Electrical function diagram for navigation mode (COMAND®) function PE82.85-P-2063-97FBA Overview of system components, telematics GF82.85-P-9999RF