[moxi]

Hey Everyone

I am really struggling with this one. Have read the dozens of threads on "No Audio" but none of them seem to match my issue.

Just for context.

- Car is a 2006 E90
- It's ex Japanese (I am in New Zealand)
- 6 Speakers, No Amp.
- No sound at all, be it warning lights, radio or anything. When I turn the volume control nothing happens.

Some pics that may help.

All the tech in the back left of the car with the carpet stripped off. I have gone through all of these and the Fiber Optic lights on these seem all fine with the normal red light.


The only thing without a light, this is loose in the boot under the carpet. Could have been something removed when it came from Japan?


However if I follow the cable, it looks like it has been looped to itself and not actually going to anything? (It's the right most cable of this pic)



The final (Or first?) piece behind the glovebox. If I take this out then that is red and fine.



Does anyone know anything more I could test etc?

Thanks Heaps!

[Captain Buumer]

Draw a schematic how the Most is wired including the modules between noting down receives y/n. Forwards signal y/n.

During this examination verify that signal passes through all modules.

Also MOST is a loop.
Master module sends out signal and other modules add information to it but it has to reach back to the master module - completeing a loop. If this loop is not complete then there is no sound.

Most likely bluetooth or the weird TCU module is not passing light along.

My car has opticals for HU and under steering wheel is one connector (that is easy to forget to connect) essentially very few modules.
With base speaker system(no amp) you should be able to eliminate all fiber going to rear - meaning instead of sending it to the rear you just complete the loop.

This should give you ideas if problem lies in the rear modules or front modules.

If hardware wise you can't find anything wrong then maybe someone replaced HU and coding is not correct.

Right now it does not look like complete loop given the information from images.

[ctuna]

What are you using for the Source of the Music ?
I thought the Jap Cars are on a different part of the spectrum
for Radio and you had to Select your frequency band for
the your Area this has come up before.
One active line to that area if there is Logic 7 two with cd changer but almost
no one has a CD changer anymore.

Usually there is only one active Most Bus Line to the amp but
if you have no amp there should be no active Most Bus
stuff to that area.

I would run your Vin through Mdecoder.com to see what it spits out.
Especially in the 6xx options that relate to the entertainment system.



What do you have for a Head unit. Its usually pro Radio or I drive in most places
as far as I know.

[moxi]

Thanks Captain, do you know what the MOST part in final picture is ? (Behind Glovebox)

I kinda assumed that could be the end of the loop and that if the light there was on then all would be good?

Cheers!

Originally Posted by Captain Buumer

Draw a schematic how the Most is wired including the modules between noting down receives y/n. Forwards signal y/n.

During this examination verify that signal passes through all modules.

Also MOST is a loop.
Master module sends out signal and other modules add information to it but it has to reach back to the master module - completeing a loop. If this loop is not complete then there is no sound.

Most likely bluetooth or the weird TCU module is not passing light along.

My car has opticals for HU and under steering wheel is one connector (that is easy to forget to connect) essentially very few modules.
With base speaker system(no amp) you should be able to eliminate all fiber going to rear - meaning instead of sending it to the rear you just complete the loop.

This should give you ideas if problem lies in the rear modules or front modules.

If hardware wise you can't find anything wrong then maybe someone replaced HU and coding is not correct.

Right now it does not look like complete loop given the information from images.