CCC - connected devices

Components connected to the Car Communication Computer (CCC)

• • Fan
    
  • MOST framework
    
  • Loudspeakers (not with Top HiFi system)
    
  • Central Information Display (CID)
    
  • Radio aerial
    
  • GPS aerials
    
  • Microphone
    
  • Video input
    

Fan

To test the fan, it is activated with maximum speed. After a startup period of 5 seconds, the speed is measured.

• Maximum speed: approx. 7000 rpm
  
• Speed > 4200 rpm => fan OK
  
• Speed < 4200 rpm => fan defective
  
• Speed = 0 rpm => fan might not be connected
  

MOST framework

In this test step, there is a check as to whether the MOST framework is currently closed. If it is determined that the MOST framework is open, the user is referred to the test module 'MOST ring fault diagnosis'.

Speaker

To test the function of the loudspeakers, test tones with the following frequencies are issued:

• 50 Hz bass tone to activate the sub-woofer
  
• 500 Hz tone to activate the medium-range loudspeaker
  
• 10,000 Hz tone to activate the tweeter
  

With a Top HiFi system, the loudspeakers are not activated directly by the CCC. In this case, the activation comes from the Top HiFi amplifier. The Top HiFi amplifier is connected via the MOST bus to the CCC.

These test tones can also be used to localise disruptive noise in the panels (rattles, clattering) caused by the loudspeakers.

CID

To check the connection from the CCC to the CID, the following tests are run.

• The fault code memory entry ”A468 external break in wiring (LVDS data line)” indicates that the LVDS data line of the CID is not connected.
  
• The CCC creates a test card at the CID. If the test card can be seen on the CID, the CID is properly connected to the CCC and is functional.
  

Radio aerials

To check function of the radio aerials, the following tests are run.

• The fault code memory entry ”DAD2 diversity not connected” indicates an interruption in the connection from the CCC to the aerial diversity.
  
• The aerial self-test is started and queried. If a fault is displayed, there is a problem with the aerial structure or the connection from the CCC to the aerial structure. The fault ”DAD2 diversity not connected” must not be entered in the fault code memory.
  

GPS aerial

This test step checks whether the GPS aerial is properly connected and functioning. The fault code memory entry ”A054 GPS aerial not connected” also indicates a problem with the GPS aerial. In the event of a negative result, the connection to the GPS aerial must be checked.

Microphone

To test the microphone, the CCC or Top HiFi amplifier issues a test tone that is received by the microphone. If a Top HiFi system is fitted, no tone can be issued directly by the CCC. In this case, the test tone is created by the Top HiFi amplifier.

Video input

The video input at the CCC is monitored by the video module