Diagnostic Instructions - Fibre Optic Cable: Check

NOTE:

Check that special tool 9512867 is working before using it. This is done as follows.

Select the desired socket for connection by setting the SELECTOR SWITCH to position 2+0 or 2+4.
Connect a suitable optical test cable, with the instrument supplied, to the selected socket
Select visual indication (green light - LED) or sound indication (buzzer - BEEP) by setting the right switch BEEP/LED in the desired position.
Set the special tool's switch OFF/ON in position ON . The red light (POWER ON) shall light up.
Press the red button (2+0 TEST or 2+4 TEST) on the lower section of the special tool which corresponds to a connected test cable. The unit now transmits a light signal through the test cable.
The transmitted signal will be received as long as there is now a complete optical loop. If visual indication is selected, the green lamp Rx will light to indicate that the signal has been received. If sound indication is selected the buzzer will sound to indicate that the signal has been received
When the check is complete, set the OFF/ON switch on the special tool to position OFF .

The following must be carried out after repairs, checks or replacement of fibre optic wiring.

Connect the desired connector on the MOST cable to the relevant socket on the special tool
Select the connected socket by setting the SELECTOR SWITCH to position 2+0 or 2+4
Set the special tool's switch OFF/ON in position ON . The red light (POWER ON) shall light up.
Activate the Infotainment system.

HINT: If the infotainment system has been activated and there is not an open-circuit in the fibre optic network, the display on the infotainment control module (ICM) must be lit.

HINT: It is also possible to check visually if there is a light signal in the MOST cable from a control module in the network to the connector for the next control module without switching on the ignition. This is done by connecting the special tool to the connector on the MOST cable at the relevant control module.

Select the socket which is connected on the special tool by setting the SELECTOR to position 2+0 or 2+4
Disconnect the MOST cable from the next control module
Set the special tool's switch OFF/ON in position ON . The red light (POWER ON) shall light up.
Press the red button (2+0 TEST or 2+4 TEST) on the lower section of the special tool which corresponds to a connected MOST cable. The special tool now transmits a light signal through the cable. Check that there is a red light at the next connector on the MOST cable
When the check is complete, set the OFF/ON switch on the special tool to position OFF .

NOTE:

The visual check is not a verification of the function of the system. However the strength of the light signal must exceed a certain level for there to be full functionality in the system.