CD73 doesn't turn on

[Repinator]

Alpine CD73 Professionnal , the cd does load and eject, the lights come on with driving lights but the rest of the radio doesn't work , no sound.
I checked all the fuse, there is 12V coming to the radio
I did not find any defects.
Can anyone help me?

[MrRepair]

Remove main PCB and turn it over. Look for 5V rail pico fuse. Its by the emitter of Q821 and is marked with a M. Its open circuit - replace. You can check the one on the 8V rail too. Its on the emitter of Q823.

[Repinator]

Remove main PCB and turn it over. Look for 5V rail pico fuse. Its by the emitter of Q821 and is marked with a M. Its open circuit - replace. You can check the one on the 8V rail too. Its on the emitter of Q823.
you were right,5v pico fuse damage.
this radio starts on the table,or just on the car?

Thanks!

[MrRepair]

You can test everything on the bench. If you get no sound the car may have an amplifier.

[Repinator]

After I deleted both eeprom cd starts but the display is visible in the fog.

[MrRepair]

Both IC512 & IC603 must be loaded. You have deleted the setup data. Can you restore the original or copy from another unit ?

[Repinator]

I have the original data, but it doesn't start with them

[MrRepair]

Try these: BMW.rar (https://www.digital-kaos.co.uk/forums/attachment.php?attachmentid=664510&stc=1&d=1572966554)

[Repinator]

With your dump it works :applause:

Thank you very much sir!

[MrRepair]

You can check everything in service mode:

Switch radio ON.
Within 10 seconds hold M button in for 8 seconds.
Service menu will display.
Navigate with + & - buttons

Be careful not make changes you don't understand.

[ThankYou]

Remove main PCB and turn it over. Look for 5V rail pico fuse. Its by the emitter of Q821 and is marked with a M. Its open circuit - replace. You can check the one on the 8V rail too. Its on the emitter of Q823.

Thank you MrRepair. My BMW Radio stopped working last week. It didnt power on anymore, but it was capable of inserting and exiting CD's. I tried your advice with Q821 and i found an smd part, which was labeled with an M, but was 1 cm away from Q821. I tested the "M" part with an multimeter and it worked, so this part wasn't damaged. After a while i saw a part with the lable "F" next to the Q821, when i tested that one, there was no continuity so i tried to bridge that part with a wire. After doing this my Radio started working again. So if the "M" part is not broken, it could be the "F" part. Thank you very much for your advice :)

[MrRepair]

You're welcome. Stay safe.

[Dr Alex]

Remove main PCB and turn it over. Look for 5V rail pico fuse. Its by the emitter of Q821 and is marked with a M. Its open circuit - replace. You can check the one on the 8V rail too. Its on the emitter of Q823.

MrRepair,what amperage should i use for this fuse?
thanks

[MrRepair]

******** 300 ma.

[electro10]

******** 300 ma.

for both fuses?

And thank you by your information, I have the same solution and was the fuse!

[MrRepair]

I use 500ma ea. for both fuses. Then never blows for no reason.

[electro10]

I use 500ma ea. for both fuses. Then never blows for no reason.

thanks by your answer. Now I only have 370mA and 1A. In your opinion, what is the most indicated?

Thank you a lot

[hsbdriver]

I also have CD73 what remains dark. No sound, no display...should I also reflash the eeproms?

[MrRepair]

No. Check the 2 pico fuses under main PCB. If it is fitted in a Mini and not BMW, fit MOST bypass loop to radio.

[hsbdriver]

Thanks !
Could you tell me manufacturer of eeprom chips?

[things4u2get]

Hi, do you by any chance please have the Mini Radio 2 CD 73 version of these eeprom dumps? BMW dumps work great with BMW front panel but Mini front panel LCD is foggy (originally tested ok). Many thanks in advance.


Try these: BMW.rar (https://www.digital-kaos.co.uk/forums/attachment.php?attachmentid=664510&stc=1&d=1572966554)

[MrRepair]

Dumps for Mini.

Mini.rar (https://www.digital-kaos.co.uk/forums/attachment.php?attachmentid=895316&stc=1&d=1655814226)

[things4u2get]

Thank you very much indeed! Your a champion!!!


Dumps for Mini.

Mini.rar (https://www.digital-kaos.co.uk/forums/attachment.php?attachmentid=895316&stc=1&d=1655814226)

[Pipee]

Remove main PCB and turn it over. Look for 5V rail pico fuse. Its by the emitter of Q821 and is marked with a M. Its open circuit - replace. You can check the one on the 8V rail too. Its on the emitter of Q823.Do you have a picture of exactly where it is on the board, I have the same problem as
Repinator

Poslano sa mog RNE-L21 koristeći Tapatalk

[BUTTOLLUCIANO]

I can't find transistor Q823. I don't know if I don't see the silkscreen or if there is no silkscreen. Can someone tell me where it is?

[BUTTOLLUCIANO]

Measured 11 ohm fuse near Q821. Shorted with test wire. The display turns on but does not write anything. Q823 I can't find it.

[BUTTOLLUCIANO]

Try writing eeprom?

[BUTTOLLUCIANO]

Do you have a picture of exactly where it is on the board, I have the same problem as
Repinator

Poslano sa mog RNE-L21 koristeći Tapatalk

Flip the PCB. Near the heatsink it is written Q821 in white on the side of the component. Q823 I can't find it.

[BUTTOLLUCIANO]

Only IC603 eeprom programmed. Now the display works. Thanks to MrRepair for the eeprom files and advice.

[yakuzi]

will be attempting to check the fuses tomorrow I hope this will fix the radio :shot:

(sorry for reviving old thread but looked through the whole internet and the only solution is here)

edit //

looks like fuse F died, M was OK:

https://youtu.be/gYQHd5HY2ic

Haven't got a clue how MrRepair figured it out, but hats off to him.

edit 2 // what potential harm I'm doing to the board by bridging broken fuse as I'm not able to find the exact one for replacement ?

[dragan68]

Today I had a case that the bmw device alpine CD73 does not work. I tried it on the bench. Turned on the power but the device did not give any signals. I checked fuse near the emitter Q821 as recommended by MrRepair in post number 2. The fuse was faulty. I bridged the fuse and the device worked. I wrote my experience that may help someone else. Of course Many thanks MrRepair.