If the command module breaks and needs to be replaced, what other features of the vehicle will no longer work?
Would the speakers, amplifier, navigation, cd/dvd player, stop working? What other features requires the use of the command module to be accessed. For example if the command module breaks then you wont be able access the Aux input, which means you cant connect and ipod.

In the case of the command module needing to be replaced, would installing a seperate speaker, amplifier and car deck work to provide music for the SL500?

 

A malfunction in any component on the fiber optic loop - which includes your COMAND - takes the whole loop down, and everything on the loop - CDC, phone, radios, voice control, tape player, amp, nav system, etc.

The exception is that an individual component of COMAND could fail and not take all else; for example, your nav CD reader in the COMAND unit could fail, and you'd only lose nav capability. But if the failure took out the ability to pass light, then all would fail.

If you replace the COMAND unit, you must also replace any of the components on the loop whose function you wish to retain - except possibly, speakers. There are such systems made - search this forum for Pioneer, Kenwood, AVIC - see what you get.

 

Does the source of the fiber optic loop pass light into a parralell circuit, this way if an individual component failed the other components still functions because the main branch of current or light is still feeding the other components?

What powers the light that is passed in the fiber optic loop, is it like a battery? I assume that if that component (battery) fails and cant source the light (current) in the fiber optic loop then it will affect the function of all your other components. If this is true, then as long as you can replace/repair the source of light (battery) then it should still pass light in the fiber optic loop?
If possible I woud rather replace the source of the light rather than the the whole command module. It would probally be cheaper to replace the soure of the light(battery) rather than the whole command module.

While the car is on does the command module display light up constantly? Can you dim the brightness of the command module display, or maybe turn it to stand by or off? I hope by doing this it would preserve the life of the command module by drawing less power from the source of the fiber optic loop? Its probally the navigation component that constantly requires a strong flow of light(current) which puts wear and tear on the source of the fiber optic loop, which causes the failer in ther fiber optic loop.