Cockpit Management and Data System (COMAND) Switch on/off behavior - GF82.85-P-0003-07TJA

Activating the overall system 

When the vehicle is opened, all data bus systems are activated to ensure a faster switch-on procedure. If the transmitter key is in position 1 (circuit 15R ON), the display of the COMAND operating, display and controller unit (A40/3) is switched on, provided that the latter was switched on before the transmitter key (A8/1) was last removed. The system that was active before the key was last removed (e.g. radio) is switched on and the corresponding main menu is displayed. If the COMAND operating, display and controller unit was switched off for more than t = 30 min, then a warning message appears at first with general information about how to use the system.

Conduct when pushing "ON" button 

The COMAND operating, display and controller unit and the display can also be switched on when the transmitter key is removed by pressing the "ON" button.

All functions are then available for t = 30 minutes

After this the COMAND operating, display and controller unit switches off automatically.

Switch-off characteristics 

The COMAND operating, display and controller unit is switched off when the transmitter key is removed (circuit 15C OFF). The run-on time of t = 30 min. (standby) of the navigation system starts.

During the run-on time, all the important localizing parameters remain stored.

The audio system run-on time can be set by customer service. The COMAND operating, display and controller unit, which is not switched on, is always on standby when the class B Controller Area Network Bus (interior) (CAN-B) is active.

Switch off characteristics at undervoltage 

In the case of battery (G1) undervoltage, a message appears on the display on the COMAND operating, display and controller unit requesting the driver to start the engine. If the engine is not started, an additional warning is output after t = 3 min, indicating that the system will be switched off in 10 s if the engine is not started.

If the system has shut off and the on-board power supply rises again, the COMAND operating, display and controller unit does not switch itself on again automatically. The system can be switched on again manually. The warning procedure then runs again, until the cause for the undervoltage is rectified.

Switch off behavior (run-on mode) when the destination has not been reached 

If the route guidance destination has not been reached, the navigation system in the COMAND operating, display and controller unit acts as follows when the engine is shut off:

• Navigation remains active up to t = 30 min. (e.g. refueling stop). Navigation continues from where it left off after restarting the vehicle.
• After t = 30 min up to a maximum of t = 2 h, the COMAND operating, display and controller unit remains in "Sleep mode". The route is re-calculated after restarting the vehicle and the navigation continued.
• After t = 2h a prompt is displayed after starting the vehicle asking whether the route should be recalculated.

  "YES" = Route is calculated again.

  "NO" = Navigation will cease.