LEMON Manuals: Even more car manuals for everyone
Home >> Mercedes Benz >> 2019 >> CLS450 Base >> Repair and Diagnosis >> Electrical >> Motors, Switches, Relays >> Electrical System - Body - 257 Chassis 2 Of 8 >> Basic Knowledge >> Navigation Mode, Function - GF82.85-P-2012FR

Navigation Mode, Function - GF82.85-P-2012FR

Model 257, 290 

up to model year 2021 

with code 531 (COMAND APS) 

G14550283Courtesy of MERCEDES-BENZ USA

Shown on model 257 

G14550284Courtesy of MERCEDES-BENZ USA

Shown on model 290 

Function requirements for navigation mode in general 

General navigation mode 

The navigation module is integrated in the head unit. The navigation system includes the following functionalities:

The location of the vehicle and the direction and distance to the destination are determined continuously with the aid of the navigation system. After entering or selecting a destination location, route calculation starts.

A range of options can be selected for route calculation according to the national version, e.g.:

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. Following calculation, the route is displayed by arrow pictograms on the Audio/COMAND display. 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.

IMPORTANT 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 card 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.

IMPORTANT Destinations can be sent from the Internet via the "Mercedes-Benz Application Gateway" to the vehicle and imported into the navigation system.

IMPORTANT Model 257, 290

up to model year 2021

with code 531 (COMAND APS)

except code 498 (Japanese version)

Routes can be sent 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 function consists of the following subfunctions:

IMPORTANT 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.

Activation and operation of the navigation system 

The navigation system can be operated with the following components:

When activating the navigation system on the upper control panel control unit, the operation signal is forwarded as follows:

LCP LIN →

Audio/COMAND control panel (except code 446 (Touchpad only)) or Touchpad (with code 446 (Touchpad only)) →

Telematics CAN →

Head unit

The Audio/COMAND control panel (except code 446 (Touchpad only)) and the touchpad (with code 446 (Touchpad only) or with code 448 (Touchpad)), sends the operation signals over the telematics CAN to the head unit.

The control signals from the head unit multifunction steering wheel button group are forwarded via the following route:

Steering wheel electronics →

Steering wheel CAN →

Steering column tube module control unit →

Chassis FlexRay 

Electronic ignition lock control unit →

User interface CAN →

Head unit 

When operating with the voice control system, voice input takes place using the driver hands-free system microphone. The words spoken are converted into an electric signal and routed to the head unit.

IMPORTANT For the voice control system of navigation, in particular for destination entry, additional name lists are available in the navigation system. Name lists exist for the following information, for example: place names for selected towns/cities on the data medium, street names for all towns, town centers and special destinations.

General information on 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 interruption of the satellite reception) 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.

GPS position finding function sequence 

On vehicles with code 362 (HERMES LTE) as of 01.06.2019, the head unit receives GPS signals from the HERMES control unit.

On vehicles with code 362 (HERMES LTE) up to 31.05.2019 and on vehicles except code 362 (HERMES LTE), the head unit receives 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.

IMPORTANT Since GPS operates in the gigahertz range 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).

General information on basic position finding 

Navigation can be continued without a GPS signal using 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 when GPS signals are received.

For basic position finding the head unit requires the following information:

Basic position finding function sequence 

For basic position finding the head unit needs signals from the following components:

The head unit receives the data from the Electronic Stability Program control unit via the following route:

Suspension FlexRay →

Electronic ignition lock control unit →

User interface CAN →

Head unit

The gyro sensor and 3D acceleration sensor data is forwarded within the head unit. The current vehicle position (longitude and latitude) is then calculated in the head unit. The basic position finding calculation is performed approx. once per second.

IMPORTANT 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. The deviation is automatically corrected by the navigation processor integrated in the head unit when GPS data is received.

Calibration 

The calibration following a tire replacement is performed automatically.

Recalibration 

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.

General information on route calculation 

Route calculation is accomplished using the options set to the best possible extent. 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 criteria and options can be displayed and changed at any time. Acoustic information is output ("Route is being calculated") and following successful calculation the route is displayed on the map.

Route guidance function sequence 

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 

The signals for visual depiction of the route guidance are generated by the head unit and sent via an HSVL line to the Audio/COMAND display. On vehicles with code 464 (Digital instrument cluster full display), the same high-resolution visual display is also shown in the instrument cluster upon request. In this scenario, the head unit also sends the picture signals to the instrument cluster via an HSVL line. The Audio/COMAND display is switched on by the head unit via the telematics CAN.

Route guidance through driving lane recommendations 

For certain turnoff situations on multiple-land exit points (e.g. freeway intersection) driving lane recommendations are shown in the bottom line. In addition, when a turnoff recommendation is given, the distance to the actual turnoff point is also displayed by means of 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 in 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:

Further voice messages take place, for example, 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. Special information is issued in some instances by voice output, for example:

The navigation processor of the head unit links word segments to form complete instructions or information during voice output. The head unit sends the voice output to the following components:

The voice output volume can be adjusted during a voice output using the volume control button in the right lower control panel or using the head unit multifunction steering wheel button group's volume adjustment switch.

On model 257 the operation signal of the volume adjustment button is sent by the right lower control panel over the following route:

LCP LIN →

Audio/COMAND control panel (except code 446 (Touchpad only)) or Touchpad (with code 446 (Touchpad only)) →

Telematics CAN →

Head unit

On model 290 the operation signal of the volume adjustment button is sent by the right lower control panel over the following route:

Drive Unit CAN →

Drive Unit control unit →

User interface CAN →

Head unit 

The operation signal from the head unit multifunction steering wheel button group is forwarded as follows:

Steering wheel electronics →

Steering wheel CAN →

Steering column tube module control unit →

Chassis FlexRay 

Electronic ignition lock control unit →

User interface CAN →

Head unit 

General information on dynamic route guidance 

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.

Function sequence for dynamic route guidance (except code 498 (Japan version) and except code 367 (Live Traffic Information) and a valid subscription for real-time traffic data) 

Incoming information on the traffic situation can be received with the Radio Data System (RDS) and Traffic Message Channel (TMC) function via FM radio or digital radio (DAB) if an appropriate station is set.

IMPORTANT Dynamic route guidance takes place through RDS and TMC if there is no valid subscription for real-time traffic data or if the vehicle is not within the geographical area for which the traffic data service is available.

Traffic messages are received as FM or DAB signals via the following route:

Rear window antenna →

FM, AM, CL, DAB and KEYLESS-GO antenna amplifier or FM 2, DAB and TV antenna amplifier →

Head unit

Function sequence, Vehicle Information and Communication System (VICS) via 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.

VICS messages are received via the following route:

Rear window antenna →

FM, AM, CL, DAB and KEYLESS-GO antenna amplifier or FM 2, DAB and TV antenna amplifier →

Head unit

In the head unit, the VICS messages are processed in the integrated FM multiplexer and then shown on the Audio/COMAND display via the HSVL line.

Function sequence for dynamic route guidance with VICS (with CODE 498 (Japan version)) 

Dynamic route guidance requires the Dedicated Short-Range Communications control unit, DSRC antenna and Vehicle Information and Communication System (VICS) control unit. 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 Vehicle Information and Communication System (VICS) control unit receives infrared signals and VICS signals in the 2.5 gigahertz reception range and forwards them via the Dedicated Short-Range Communications control unit 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. The navigation processor makes the decision whether the route should be changed. If necessary, a message saying that the route was changed is issued.

Additional function requirements for dynamic route guidance with real-time traffic data over the HERMES control unit (with code 367 (Live Traffic Information) and a valid subscription for real-time traffic data) 

IMPORTANT At the end of the subscription or outside of the geographical area for which the traffic data service is offered, only the dynamic route guidance with radio traffic messages is available.

Function sequence for dynamic route guidance with real-time traffic data through the HERMES control unit (with code 367 (Live Traffic Information) and a valid subscription for real-time traffic data) 

The HERMES control unit receives the real-time traffic data over the emergency call system 1 antenna (model 257), the telephone antenna splitter, left telephone antenna and right telephone antenna (model 290) and over the emergency call system 2 antenna from the service provider.

The HERMES control unit forwards the real-time traffic data over a wireless connection through the WLAN antenna to the head unit. The HERMES control unit receives position data from the head unit at regular intervals. Data exchange between the HERMES control unit and the head unit takes place via a wireless connection between the integrated WLAN interface of the HERMES control unit and the WLAN antenna.

The head unit cyclically sends the position data over the WLAN antenna that are received by the HERMES control unit and forwarded to the service provider over the emergency call system 1 antenna (model 257), telephone antenna splitter, left telephone antenna and right telephone antenna (model 290) and over the emergency call system 2 antenna. In this way, 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:

Extended navigation functions 

The navigation system is extended with regard to convenience, customization and tourist information by the following functions:

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 implemented internally in the head unit and, where applicable, shown via the HSVL line on the Audio/COMAND display.

  Electrical function diagram for navigation mode (COMAND) function   PE82.85-P-2063-97XBA
  Overview of system components, telematics   GF82.85-P-9999FR 
scientia non olet · About LEMON Manuals