Flap Central Information Display (CID)

Flap Central Information Display (CID)

The Flap Central Information Display (CID) is a folding LC display. Defined positions are set automatically by means of electric drive. In addition, positions can be changes using switches. Positioning by hand is also possible.

The Flap Central Information Display (CID) is the central display unit for the scope of functions:
- Navigation (option with Telematic BMW ASSIST)
- Radio
- CD / MD
- On-board computer (BC)
- Audio
- Television (not while the vehicle is being driven)
- CD changer
- Telephone

Prerequisite for the socket of the Central Information Display (CID) is that the following components are fitted:
- MD/CD 53 CID operating unit (CID, operating unit of the Central Information Display)
- Navigation computer
- Wiring harness for Navigation High
- Telephone (option)
- Video module (option)
- CD changer (option)

Brief description of components

K-bus
The K bus (Body Electronics) is used for data exchange between the control modules of the body electronics and the microprocessor of the Flap Central Information Display (CID). Data is exchanged by means of data telegrams.

D Bus
The D bus (Diagnostic Bus) is used for data exchange between the control module of the Central Information Display (CID) and a diagnosis tester. Data is exchanged by means of data telegrams.

MD/CD 53 operating unit
On the high navigation system, the MD/CD 53 operating unit (CID radio) is the operating unit for the Flap Central Information Display (CID). The MD/CD 53 operating unit (CID radio) communicates with the microprocessor of the Flap Central Information Display (CID) and other control modules via the K bus. Data is exchanged by means of data telegrams.

The MD/CD 53 operating unit (CID radio) is fitted in the center console beneath the center fresh-air vent.

Flap Central Information Display (CID)
The Central Information Display (CID) consists of:
- LC display (6.5" Advanced TFT display) with LCD backlighting and a control module (microcontroller) located behind it
- Electrical drive with cross-winding motor (collectorless direct current motor) with transmission gearing, two axles and bearings
- Recess (securing frame) with two switches

The LC display is an analog display. The LC display is activated with RGB and K bus signals. At the output, it issues K bus telegrams for processing by the navigation computer and the video module. The LC display has a function for automatic adjustment to the ambient light. The LC display with the control module is fitted in a case secured to an axle. The case on the axle can be swiveled by means of the electrical drive between 0 degree and 108 degrees. The positions of the LC display are detected by Hall sensors on the transmission gearing. The case and drive are fitted in a recess (holding frame). Data is exchanged by means of data telegrams.

The Central Information Display (CID) is fitted in the dashboard above the center fresh-air vent.

Lights switching center (LSZ)
The lights switching center (LSZ) provides the information for the brightness setting on the LC display. For this, information from various sensors is processed. Data is exchanged by means of data telegrams.

Main functions

Standby
As of terminal R On (or with corresponding K bus telegram), the Flap Central Information Display (CID) switches on and is powered up.

The LC display and the LCD backlighting are switched off when there is no signal on the bus for 30 seconds (after the bus goes to sleep).

Voltage supply
The operating voltages for the Central Information Display (CID) are generated from the vehicle voltage and monitored from under- and overvoltage.

Undervoltage: In the case of a vehicle voltage < 9 V, the Central Information Display (CID) is switched off. With a vehicle voltage > 10 V, it is switched on again automatically.

Overvoltage: In the case of a vehicle voltage >17 V, the Central Information Display (CID) is switched off. With a vehicle voltage < 16 V, it is switched on again automatically.

Temperature monitoring / overtemperature cut-off
The temperature value established by the Central Information Display (CID) by means of a temperature sensor on the LC display, as well as other data, is used for brightness control. When "excess temperature" is reached, the LC display is switched off.

Overtemperature is reached when the value obtained through the temperature sensor exceeds a threshold value stored in the Central Information Display (CID) for a defined period.

The state of the LC display is checked in cycles by the Central Information Display (CID). After the LC display has cooled down to operating temperature, it is switched on again.

Brightness control (lighting and instrument dimmer)
The brightness control on the LC display is implemented via the lights switching center (LSZ). Here, values determined by sensors, stored parameters and manual inputs via the dimmer wheel are included in the calculation.

The lights switching center (LSZ) provides the brightness setting of the dimmer wheel as a power PWM signal (terminal 58g) and as a telegram on the K bus. The value of the K bus telegram reflects the angle of rotation of the dimmer. The change between day and night mode is derived from the K bus information.

The backlighting brightness is influenced by
- the surrounding brightness determined by the photosensor in the Central Information Display (CID),
- the position of the dimmer wheel and
- the temperature on the LC display.
To ensure good legibility of the LC display at low temperatures, the brightness is compensated; at high temperatures, the brightness is weakened.

In the case of brightness control, a distinction is made by means of stored threshold values for the photosensor and dimmer wheel between the normal brightness setting during the days and the following special case. At ignition lock position I with the light switched off and the TV switched on, the minimum "light off" display brightness is set to "day min (TV)".

IC display positioning
Automatic positioning: The Central Information Display (CID) is folded up or down automatically when a function of the Central Information Display (CID radio) is activated. The activation is triggered at the Central Information Display radio (CID radio) via the right-hand rotary pushbutton (DDK) "Navigation ON/OFF" or the left-hand rotary pushbutton (DDK) "Radio ON/OFF". Exchange of information takes place with data telegrams via the K bus.

For the LC display, the following positions are defined:
- 0 degrees position: Resting position; the display is folded downwards into the recess
- 30 degrees position: minimum position
- 100 degrees position: normal position
- 108 degrees position: maximum position; the display is complete unfolded

When switched on, the LC display is first moved into the "Last Function Memory" position. When terminal R is disconnected, the Central Information Display (CID) is always folded up and the last position is stored.

Last Function Memory: This function means that, when the system is started up, the Central Information Display (CID) resumes the function last set on the system prior to switching off. Depending on the last stored position, when the ignition key is inserted the following occur:

As of ignition lock position I (terminal R On) and LC display previously folded down: The LC display is automatically returned to this position (Last Function Memory position), as the navigation menu also restarts with the last detected menu.

As of ignition lock position I (terminal R On) and LC display previously folded up: A distinction is made between two cases:
- Route guidance (navigation) was switched on (route guidance voice output continues even if the LC display is folded up). The LC display must fold up again automatically (menu item "Resume route guidance" appears on the LC display).
- Route guidance was switched off and the LC display folded up. The LC display remains folded up until operation of a button/DDK on the CID operating unit causes a change in the information content of the LC display (not, for example, volume control) or the "Open/Close" switch on the recess is operated.

Fine adjustment with switch: From the "Last Function Memory" position, manual positions changes are possible. The inclination of the LC display can be changed to improve legibility. The left-hand switch on the recess can be used to change the inclination in 1.2 degrees steps in the range from 85 degrees to 108 degrees. The signal from the switch has a direct effect on the servomotor. The new position is stored.

Folding up and down with switch: The LC display can also be folded up and down using the right-hand switch on the recess. If the LC display is folded up manually or electrically while the vehicle is being driven, the LC display remains closed when the next trip is started (Last Function Memory position). The LC display must then be folded down using the right-hand switch.

Manual positioning: The LC display can also be folded down or up directly by hand without switch operation. The position of the LC display can also be changed manually when folded down. The last valid position is stored. In the case of movement by hand beyond 30 degrees towards 0 degrees, the LC display is folded up automatically. In the case of adjustment by hand from 0 degrees towards 108 degrees, the LC display automatically moves to the previously valid position after the limit of 30 degrees is exceeded.

Notes for Service department
In the event of a failure of the navigation computer or the video module, the LC display background light is switched off. The "screen off" mode is activated. After 30 seconds, the LC display is folded up. The fault is stored.

Safety functions
The positioning of the LC display is stopped by anti-trapping protection when
- the positioning sequence is blocked by an obstacle or
- the ignition key is removed during the positioning.

The LC display stops in the position reached and the position is stored. The position of the Flap Central Information Display (CID) can only be changed by operating the right-hand switch or folding down by hand. The obstacle that caused the deactivation must have been removed beforehand.

Diagnosis
The information stored in the fault memory can be read out via the diagnostic bus with the diagnosis tester.