Function
Function
control module
The DVD player is used to transfer map information to the hard disk. The map information on the hard disk is used to navigate. The Multimedia module (MMM) has several user functions, such as:
- route guidance, i.e. guidance to a specific target (address, a specific hotel etc.)
- show map
- find a hotel, a car park, a shopping mall, in the surroundings or in the vicinity of a specific place
- show TMC information, i.e. traffic information (traffic jams, closed roads etc.)
- show remaining mileage and estimated journey time to selected destination.
- system settings for navigation
The start menu allows the user to choose whether the system is to start in a Beginner or Advanced user setting. In the Beginner user setting, only the most important functions are available and are intended for beginners. All functions are available in the advanced user setting
The navigation menu and quick menu display, on the monitor, all the functions that are available for the user to use.
Certain functions can be configured by the user in system settings. These functions are:
- type of route guidance (fastest route, shortest route or easiest route)
- avoid ferries, toll roads etc or not
- volume voice guidance
- language.
Menu navigation
The on-screen menu can be controlled using the navigation buttons on the reverse of the steering wheel (16/46).
The buttons consist of:
- an enter button
- a back button
- a control button that can move the marker on the screen up, down, left and right.
The commands are transmitted from the Steering wheel module (SWM) (3/254) via CAN to the Central electronic module (CEM) (4/56) and on to the Infotainment control module (ICM) (3/281) on the CAN network. The Steering wheel module (SWM) converts the electrical signal to an optical signal and sends it on to the multimedia module (MMM) (16/108) via the MOST network.
The remote control for the Multimedia module (MMM) has the same functions as the steering wheel buttons.
Navigation
The navigation section in the Multimedia module (MMM) (16/108) calculates the vehicle's position from the information from:
- GPS antenna (16/47)
- wheel rotation counter
- the gyro in the multimedia module (MMM)
- reverse gear status
- map matching function.
Information from other nodes that is used for navigation:
- wheel rotation counter from the brake control module (BCM) (4/16)
- reverse gear status from the transmission control module (TCM) (4/28) and central electronic module (CEM) (4/56).
Information from these control modules is sent to the infotainment control module (ICM) (3/281), which then distributes the information to the multimedia module (MMM).
Information from the gyro and the wheel rotation counter is used to achieve better precision than the GPS position from the GPS antenna can give, and is used for dead reckoning, i.e. to calculate the position when communication is lost with the GPS satellites. This occurs when in a tunnel, for example.
The navigation function indicates current position and how to get to the specified destination. There is also voice guidance, which tells the driver which way to drive to get to the specified destination.
The navigation buttons on the steering wheel module (SWM) (3/254) are used to control the on-screen menu for navigation.
Two signals are sent via the high speed side of the CAN network to the central electronic module (CEM):
- information from the wheel rotation counter is sent from the brake control module (BCM)
- information on reverse gear status is sent from the transmission control module (TCM)
The central electronic module (CEM) transmits both signals to the infotainment control module (ICM) via the low speed side of the Controller area network (CAN). In turn, it sends the signals on the MOST network to the Multimedia module (MMM).
Information for voice guidance to the selected destination is sent between the multimedia module (MMM) and integrated audio module (IAM) (16/1) via the MOST network.
In order for the Multimedia module (MMM) to select a route and display the position of the car, the map information must be on the hard disk. The Multimedia module (MMM) calculates the position and displays it on the directly connected screen. If the map information has been updated, the DVD must be left in the DVD player, otherwise the map information will not be displayed.
GPS reception
The multimedia module (MMM) (16/108) receives GPS signals from the GPS antenna (16/47) to the integrated GPS unit for position determination.
The information about the vehicle's position is continuously transmitted from the Multimedia module (MMM) via the MOST network to the Phone module (PHM) (16/60) for the Volvo On Call function.
A telephone number can also be sent from the Multimedia module (MMM) via the MOST network to the Phone module (PHM), to make a call to a hotel for example.
For further information, see Design and Function, Phone module (PHM).
TMC reception
The multimedia module (MMM) (16/108) receives traffic information messages (TMC) via the TMC receiver. The signal is transmitted via the antenna amplifier (16/16). Traffic information messages (TMC) are displayed on the display screen (16/46).
TMC is a standardized code system for traffic messages, e.g., information about road construction. The information is shown on the screen and is also used by the navigation function for guiding and if possible avoid closed roads and navigate around back-up traffic (dynamic route guiding).