Blaupunkt Radio removal - frustration

[heinsbush]

Hi friends,

I have been trying to remove my Blaupunkt Frankfurt radio for the last hours. This is frustrating - I still couldn't get it out and pretty much all my fingers and hands are bleeding.

Please have a look at the pictures.

- I have removed all knobs, faceplates, etc.
- I was able to slide away the bracket where it is held in place in the back...

But:
- I still can't get it out as there is not enough space to push it backwards to slide it to the side and out...
- There is still a mounting bracket on the face, but its impossible to remove it, again as there is not enough space to push the radio backwards... even then, I doubt I can slide the radio through the opening as its likely too big...
- Is there a way to remove the long shafts where the knobs are mounted?

Desperately needing some help here.
Thanks
Heinz

[Charles 230SL]

hello Heinz, have you looked at the Tech Manual? Your radio is removed through the front of the dash by taking the dash plate loose. The radio is removed along with the dash plate. Go to this link and scroll to the end for "Radio Removal": https://www.sl113.org/wiki/Electrical/Radio

[Bobmog]

Hello Heinz,
I believe if you can remove the nuts on the 2 stems, (the one with orange/brown paint) and the other one on the other stem you will be able to remove the face plate separately from the radio and both pieces will come out through the hole in the dash. Good luck!
Bob

[heinsbush]

Thanks All!

I finally got the radio out. What a pain, as I needed to remove the aircon unit in order to get the dash plate out.

The wiring is really strange.

1. There is black cable coming from the front engine bay (passenger side) directly (without a fuse in the engine bay) through the firewall into the AC harness. Out there comes a cable going into an inline fuse which on the other side has a thicker yellow cable. I gave 12V to the fuse to see if the radio comes on. But guess what, the fuel pump turned on!!!

2. The power supply to the radio is actually coming from the cabin light! From the cabin light into an inline fuse (which was burned) into the radio.

3. I gave 12v directly to the radio and it turns on. However, no sound at all, despite speaker connected. I can hear a low humming in the speaker when the radio is on, but the humming does not change even if I turn up the volume. Either radio / amp or the speaker is the issue.

Thanks for any hints.

Heinz

[Pawel66]

As for the correct radio wiring, you can find it in one of my posts when you search "radio wiring" .

https://www.sl113.org/forums/index.php?topic=27466.msg197177#msg197177

As for the radio operation - no idea, maybe it just requires repair.

You also may need to hook the antenna when checking.

[heinsbush]

Hi All,

and Thanks! So I got the radio to work - the antenna cable was not 100% snug and after a bit playing around I finally heard music.

Last issue - the volume is super low. The volume knob works smoothly from low to high (no crackling or "jumps"), it's just that the maximum volume is waaay to low.

I'm definitley not able to see in the amp what could be wrong... need to check for a repair opportunity in Germany.

[66andBlue]

Heinz:
Did you hook it up to the 4 Ohm dash speaker?
https://www.koenigs-klassik-radios.de/lautsprecher/spezial-lautsprecher-fuer-mercedes-benz-110-111-112-113/a-31122/
For repairs call Königs, you can't go wrong.
 

[heinsbush]

No - the original speaker is still inside. I measured continuity and 6.3 Ohms, so my conclusion was that the speaker is ok and its the "amp"...

maybe I can find a different speaker somewhere around the house just to test if the volume is higher...

[Pawel66]

Yes, try with new 4 ohm speaker if the nominal resistance is 4 ohms.

[66andBlue]

I have a Blaupunkt Frankfurt (W Serie) radio in my 1964 230SL hooked up to the original speaker and the sound is loud enough considering that the radio only puts out 20W at best.
If you try another speaker make sure it has an impedance of 4 Ohm, measuring resistance doesn't tell you.
If you measured 6.3 Ohm resistance then you most likely have a speaker with nominal 8 Ohm rating. Here is a useful guide:
https://soundcertified.com/how-to-tell-impedance-of-speaker/


{Note: I have moved this thread to a more appropriate Board}