Fusebox: how could I messed up the TCU?

[FatboyDean]

Hi all,

I have a 2008 135i M sport
I was trying to figure out why my front 12V power supply not working, so I went on n checked a few of them fuses, however I think I misplaced some of them which caused my telematics module/amp not working any more.

The symptom I got: SOS error, no sound in stereo, aux greyed out. I know the headunit is working fine cos I can insert a cd and it reads, just no sound! Also the TCU in the trunk does not seem to have power cos the fans not moving at all.

I took a pic of my fusebox, feel free to point out which fuse(s) were in the wrong place, I checked all of them seemed OK not blown. I also checked the following 14, 15, 18, 19, 27, 42, 56 and 63 cos from what I can find online those are for audio related functions.

This has been bugging me for a few days now. Thanks so much in advance!

[FatboyDean]

Some update:

1. I have tried to loop out the telematics control unit with an optical bypass, still no sound.
2. I notice the 'no chime, no sound' symptom was more like the amp is not working at all so I searched the forum and found my logic 7 amp (shown in pic)
3. I tested the harness and found the constant 12v supply was there (red and brown wires) so power supply to the amp is fine. However the fans on the amp was not turning, I guess either the amp is gone or the signal to turn on the amp was not set.
4. Tested all audio related fuses, they all working, not a signal blown one.

At this point I do not know what else to do, I am thinking of going back the fues box and try to match an existing working layout. So if you have an 2008 135i with logic 7 option, pls help to post your fuse box pic, I will try to match one by one.

Thanks!
Dean

[FatboyDean]

Another update:
I can trace the 'red light' from the MOST terminals in different devices:
1. The plug goes to the AMP has red light, AMP can power on but LED blinks yellow.
2. The plug goes to the GSM/Telematics module as red light
3. The plug goes to the Sat radio has red light.
4. The diagnostic port under driver seat has no red light.

Even though I used a bypass loop on the Sat radio plug, there is still no red light on the diagnostic port.

I am getting another set of bypass loop tomorrow.

[FatboyDean]

Issue resolved: my car was Apr 2008 model so it actually needs Fuse 31 to be populated unlike the Post-Sep 2008 models. So the lesson to be learned is to take a pic before touching the fuse box.