GF82.61-P-0003-02TX Audio 50 APS Switch on/Off Behavior

GF82.61-P-0003-02TX Audio 50 APS Switch On/Off Behavior
- with CODE (525) MB Audio 50 APS radio

Activation of entire system
Position 0 "key in ignition" In order to ensure a quicker switch-on process, only the bus systems are activated for 3 minutes by inserting the transmitter key (A8/1) into the EIS (EZS) control unit (N73), in position 0 (circuit 15C ON). If the radio control panel and navigation unit (A2/56) is switched on using the "ON/OFF" button, the automatic shut-off takes place after 30 minutes.

Position 1 "radio position"
Turning the transmitter key (A8/1) to position 1 (circuit 15R ON), switches on the radio control panel and navigation unit (A2/56), provided that it was on before the transmitter key (A8/1) was last removed. It remains in operation until the transmitter key (A8/1) is removed again.

The function options are limited to:
^ Operation of the radio control panel and navigation unit (A2/56)
^ Multifunction display (A1p13) in the instrument cluster (A1)
^ Operation via multifunction steering wheel

Position 2 "Ignition ON"
All the functions in the vehicle are operational by continuing to turn the transmitter key (A8/1) into position 2 (circuit 15 ON). The system which was active before it was last switched off (e.g. radio control panel and navigation unit (A2/56)) is switched on and the corresponding basic menu is displayed.

If the radio control panel and navigation unit (A2/56) was switched off for longer than t = 30 min, a warning menu containing general information on how to operate the system is displayed.

Position 3 "engine start"
If the transmitter key (A8/1) is in position 3 (circuit 50 ON), the engine is started. However, if there is a significant voltage drop during engine start, the system switches off for the duration of the engine start; after the on-board electrical system has become stabilized again, it switches on again.

Procedure for operating the "ON, OFF" button
The radio control panel and navigation unit (A2/56) can also be switched on when "circuit 15C OFF" by using the "ON, OFF" button. All functions of the Media Oriented System Transport (MOST) are then available for t = 30 min. The system switches off automatically once this time has elapsed.

Switch on/off behavior with telephone call or SMS
As the result of an incoming telephone call or SMS, the Universal Portable CTEL Interface (UPCI [UHI]) control unit (N123/1) is activated during the run-on time and conducts a wake-up pulse via the MOST. The system components are "awakened", the MOST system is operational. If a shut-off has taken place after t = 30 min, the system can be switched on again by operating the "ON, OFF" switch. The cycle of 30 minutes then starts from the beginning. The system is either switched off using the "ON, OFF" button or when "circuit 15C OFF". A phone call is not interrupted by removing the transmitter key (A8/1). In this case, the MOST system switches itself off after the telephone call has been completed.

The radio control panel and navigation unit (A2/56) is switched off when "circuit 15C is OFF". It is always in "Stand-by" mode, if the Controller Area Network bus class B (interior) (CAN-B) is active.

Conduct of radio control panel and navigation unit (A2/56) with battery voltage less than 11.5 V
If the battery voltage drops below 11.5 V (battery warning threshold), a message appears in the display and requests that the engine be started. If the engine is not started up, a warning is issued after t = 3 minutes have elapsed indicating that only approx. 10 s remain to switch the engine on before the unit is run down. In this case switching on the engine prevents the system from being automatically shut down. If the system has shut off and the battery voltage increases to more then 11.5 V again, the radio control panel and navigation unit (A2/56) does not switch itself on again automatically.

If the system has been shut down, it can be switched back on again manually. The warning procedure then ensues for as long as the fault is not eliminated.

Conduct of radio control panel and navigation unit (A2/56) with battery voltage less than 9.5 V
The radio control panel and navigation unit (A2/56) is automatically set into a defined standby condition, in which only the battery voltage is monitored. In addition to this the current operating status is stored. The radio control panel and navigation unit (A2/56) cannot be operated or accessed using STAR DIAGNOSIS in this condition. Communication with external components does not take place.