BMW Business E46 2004 (Alpine) problem

[omglol]

Hello!

My friend has a BMW E46 (2001) with Reverse radio. He bought Business CD radio (Alpine, 2004) and Fakra antenna adapter. The problem is that we can't get FM reception. CD player and MW/LW reception work OK, however, FM stations are completely dead, not a single tone. I tried setting the radio on max volume and plugging&replugging antenna at the same time. On MW/LW stations you can hear "cracking sound", but on FM you can't hear anything at all. Radio was bought from USA, but we coded it on European stations, of course.

What could be wrong? Burnt FM receiver? Any solution?

Thanks!

[zabra]

check the voltage on tuner legs
8v maybe missed or other voltage

[omglol]

Hi!

Can you please be more specific? I will post a picture of the PCB of the radio here. Many thanks!

[zabra]

fm + vdd 5v vcc 8v is printed on circuit

[omglol]

This is a brief picture of the inside (probably won't help a lot): http://dl.dropbox.com/u/2523271/20022011080.jpg

This is a picture of radio connectors: http://dl.dropbox.com/u/2523271/20022011082.jpg

Main connector is present in car, two smaller ones are not present (but that should not be the problem, as they are for Sound System and CD-Changer - he does not have either of them).

Can you tell me which part of PCB should I look into? Thanks!

[omglol]

fm + vdd 5v vcc 8v is printed on circuit

Can you mark on the picture where? Thanks!

http://dl.dropbox.com/u/2523271/20022011083.jpg

[zabra]

you dont have a wiring problem
your problem is in the main board of the radio
mw is ok : voltage is present on mw vcc leg of tuner
no voice at all on fm, 8 v is missed on pin fm vcc
follow the voltage from this point

[zabra]

you must remouve the cd mechanism
and the main board from the metal case

[omglol]

Yes, I understand, but I can't find those pins on PCB? Can you help me?

Here are two new pictures:

http://dl.dropbox.com/u/2523271/20022011085.jpg
http://dl.dropbox.com/u/2523271/20022011084.jpg

Thanks!

[zabra]

please photo of the bottom side of printed circuit

[omglol]

I've taken mainboard out. Here is a pic from the other side:

http://dl.dropbox.com/u/2523271/20022011086.jpg

Which pin are we looking for, FM+B?

[zabra]

this is the point for test
sorry i forget fm+ under the 2 other point
pin number 5 from down

[omglol]

Ok, so:

VCC +5V should have +5V.
VCC +8.3V should have +8.3V.
FM+B should have +5V or +8.3V?

If any of those pins don't have desired voltage, what to do? Thanks!

[zabra]

fm+ 8 v follow the voltage from the missed voltage point
you have to discover the bad part : switshing transistor or regulator
some times its a bad soldering
it is not easy to discover solution without having
the radio on my table
i tryed to help you as i can
good luck

[omglol]

Thanks so far! I will try to take closer look next weekend. Will report!

[omglol]

I think I've found the problem - one of the transistors is burnt. Do you know exact part number perhaps? Thanks!

Picture: http://dl.dropbox.com/u/2523271/20022011089.jpg

[omglol]

Is it possibly this thing: DTB123YC pdf, DTB123YC description, DTB123YC datasheets, DTB123YC view ::: ALLDATASHEET ::: (http://pdf1.alldatasheet.com/datasheet-pdf/view/36428/ROHM/DTB123YC.html) ?

[zabra]

please look pm

[zabra]

the transistor burned is the same that behind
F 52 PNP it must swith 8v to tuner

[omglol]

Thank you very much! I have ordered transistors ... will report if my repair sucseeded.

[omglol]

Hello!

I have changed the transistor, but no joy. FM receiver still does not work. What else could be wrong?

Voltage measurements: http://dl.dropbox.com/u/2523271/25022011098.jpg

[zabra]

after you change the transistor did you check if the 8 v is present on fm+?
if not : there is something between this transistor and the tuner cutting the voltage
if yes : there is fault in the tuner board

[verica]

add direct 8v to the tuner too see if it works and than try to find solution

[omglol]

There is 8V on FM+, so looks like tuner is bad. :(