[ctuna]

Did you mean Amp?
If you meant Amp the first thing to check is did it drown
do to water leaks.
You also need to know if you have a Hi Fi or Logic 7 Amp.

[flyrr100]

See the post I submitted today. Not promising it'll work for you, but I held the CD eject button in for 30 seconds and it reset the entire sound system.

[JamineTJ]

Just here to bump this!!! After trouble shooting all fuses, checking all MOST fibers, checking amp etc. the ONE thing that worked was disconnecting the battery and reconnecting. Can’t believe it was that simple. Thanks so much for this!

[yakuzi]

Hi folks (apologies for bumping the thread), having some issues with radio on my 09' e90. The radio died while listening to the song. Before it turned off there was a high frequency white noise for split second, the twist is that it's not completely dead, I pulled it out and checked the voltage on the connector and can confirm that there is 12V on pins that supply power to it. The buttons are illuminated, it seems like it doesn't want to boot fully. There is no chime sound too when I disconnect the seatbelts. Would anyone know how to troubleshoot that case ?

[ctuna]

You have not identified your system .
The Head Unit is not the system unless you have the base model .
The Head Unit could either be idrive or pro radio in the US there
are more options in Europe.
The system is the amp and speaker or lack of amp .
Base system has no amp
Hi Fi and Logic have amps and the common failure is death
due to drowning from clogged drains usually .
The amp is behind the US Driver side rear wheel under the trunk floor.

There are many threads here that go into detail it's one of the Most reported problems.

[yakuzi]

I looked through plenty enough of threads. Most of them relate to weak battery / radio not powering on on start of the car or simply "resetting" modules by disconnecting the battery for short period of time. Which could point to IBS cutting of some circuits. In my case the radio in question is 'Professional' model no. CD73. I have no AMP as far as my understanding goes. My radio in contrast to most of the threads here has power supplied to the unit (at least on the pins). The buttons on the radio are illuminated.

Is that enough information to even start guessing what could be wrong ?

edit//

most related solution to my problem I found is this thread https://www.digital-kaos.co.uk/forum...oesn-t-turn-on and the guy attempting to fix it here:

I will be attempting the above tomorrow and post the results here