No sound from Radio

[Olazz]

Guys, I have a '68 280 with a Becker Grandprix that has been working perfectly for last 4 years.

Car not been driven since Sept last year, so took it out for a spin over the weekend. Started on the button and drove as beautifully as ever.

Now whilst waiting for SWAMBO to do a bit of shopping, I turned on the radio,  the radio light comes on, the auto aerial powers up, but just no sound from the radio. No stations picked up on any waveband... L, BC, SW, FM, FM  Nothing has been touched or moved in the car since Sept last year.

Without stripping out the radio and speaker, which I'm reluctant to do, am I missing an obvious "trick" somewhere?

Thanks.

[WRe]

Hi,
maybe the speaker socket has come off.
...WRe

[JJP]

Hello!
Initially you can check whether the antenna cable with plug connection does not slipped out of the nest
Cheers

[Olazz]

Ok done some rooting around.

Removed the glovebox and the radio. All seems to be in order with no wiring out of place. The speaker seems to be connected directly to the amplifier that sits on bulkhead in the passenger footwell. That too is all connected.

The aerial was connected to the radio.

All powers up and radio lights come on. there is no crackle or hiss coming from the speaker at all.
Is the amp separately fused? cant find any additional fuses. The two fuses for the radio and the power antenna on the passenger side by the voltage reg are all ok.

Am stumped !

[andyburns]

The separate amp has its own internal fuse.  I would start here.  While you have it open pay attention to any unusual acidic type smells and have a quick look for any signs of melted components.  Dont stress to much about it the amps are very basic and quite easy to repair.  I just had mine completely overhauled for around 50usd.  Replaced all the electolytic caps which are usually quite tired.

[Olazz]

Ah, thanks Andy. Will have a look at that over the weekend and see if thats the cause.

Much obliged

[Olazz]

Ok I managed to look at the Amplifier today. Internal fuse is OK. `Looks brand new inside with no corrosion or damage of any kind.

So am at a loss to know what to do now.

Anyone on here have any bright ideas??

Thanks

[66andBlue]

Is the speaker dead?? Did you test it with another source?

[scoot]

On the back of your radio there should be a black plastic plug plugged into a DIN socket.  That plastic plug covers the DIN socket to which you can connect an optional cassette player.  If the black plastic plug is loose or missing, you will get no sound as the black plastic plug has a pass-through for the radio-out to the amp-in.    Do you have the black plastic plug, and is it in place all the way?

[Olazz]

@blue

Yep tested the speaker and its not dead!


@ Scoot

Now I don't recall seeing a plug on the DIN, but then I wasn't looking for one. Will have to take the radio out again.

All rather odd as the radio was working perfectly when the car was garaged in Sept last year.

Will report back.

Thanks for the help thus far chaps.

[scoot]

Now I don't recall seeing a plug on the DIN, but then I wasn't looking for one. Will have to take the radio out again.

This is a radio with a separate amp, correct?  amp failures are rare and radio failures are more typically a blown fuse or decline in functionality.  _no_ sound is as if there is no audio input, which the plug in the back would explain.  Attached image shows you what you are looking for.

[Olazz]

This is a radio with a separate amp, correct?  amp failures are rare and radio failures are more typically a blown fuse or decline in functionality.  _no_ sound is as if there is no audio input, which the plug in the back would explain.  Attached image shows you what you are looking for.

Thanks Scot, my radio is the middle one.  Is the 4-pin shorting cap the thing I'm supposed to have plugged into the DIN plug?

I will have to pull it out again and have a look see.

much obliged

[scoot]

Thanks Scot, my radio is the middle one.  Is the 4-pin shorting cap the thing I'm supposed to have plugged into the DIN plug?

Yes.  The shorting cap must be plugged in.  It is 4 pins for stereo radios and 2 pins for mono.  OR you have to have a becker tape deck plugged in.  Or you can have an aux in jack plugged in that has a switchbox integrated into it so that you can play your mp3s etc.   Basically that plug routes the audio out to the audio in and you can stick something in the middle (like a tape deck) but whatever you stick in the middle must know to complete the short out circuit when it is not in use.  (Such as the becker cassette deck will just act like the short-out pins if you don't have a tape in it).

You can buy an MP3 input to plug into that on ebay for around $40 - $50.  MAKE SURE you get one that is for stereo and that has a switch box.  Not just a cable with a 1/8" plug on the end.   If you had one of those you could tell if your tuner is dead for some reason.

Also, is it possible that you have accidently switched the radio to a band that is not relevant in your country?  For instance if I switch mine to SW I won't get anything (but I think I would still get static...)
Scott

[Olazz]

Ok my mistake, My radio is NOT the Stereo version I though it was.

It is mono and does not have a std DIN plug in the back, but a much smaller plug for Aux input.
There is nothing plugged inot the input and certainly no shorting plug.

Doesn't seem to be anything laying in the dash either that may have come off the radio.

This is what I have:
http://www.beckerautosound.com/Classic/Grand.jpg

I'm assuming that its either the radio or the amp or both that have now packed up!

[scoot]

My radio is NOT the Stereo version I though it was. It is mono and does not have a std DIN plug in the back, but a much smaller plug for Aux input.
There is nothing plugged inot the input and certainly no shorting plug.

You happen to have the only radio I don't have at my fingertips.  My brain says that the item shown as 2 in the diagram is the din plug and should have a plastic cap with 2 shorting pins (instead of 4) plugged into it.   Could you take a picture of the back of your radio (and the front please) and post?

I apologize in advance for asking what may sound like a really silly question, but are you absolutely sure that your car doesn't have either a tape player or a MP3 jack somewhere in the car?  If the plug came out when you removed the radio that would explain everything... 

[Olazz]

Hi Scott,

The top plug is a small DIN type. But there is nothing to indicate that there was anything plugged into it.

The radio stopped working before I removed it to have a look at the problem.





There is definitely no external jack anywhere in the vehicle.

[scoot]

I don't mean the little tiny brown DIN on the lower right of the back side.  I mean the other one on the upper right of the backside.  Attached is a picture of the aux in on a Europa Mono from the same time period.  It shows the DIN plug for a mono aux in and the cap.

I have no idea if that is what the plug is in your upper right, but someone should know the answer to this.  I wish I had the same radio in front of me, it would be much easier to tell then.  I certainly doesn't look like yours had a plastic plug cover ever attached there...

[Olazz]

Yep I get that we're talkig about the same plug.

It's a 6 pin DIN plug and according to the blurb , that is the AUX in. None of the photographs I have seen of the Becker GrandPrix have a cover or plug over that 6 pin DIN.


As the speaker is working I guess the radio is the problem then.

[scoot]

Well I'm stumped.  At this point I guess someone needs to bench test it with a different amp and see if it's the radio or amp.  If you were local I would be happy to loan you an amp but you are far away...

[Olazz]

Thanks for taking so much time to try and help me out Scott.

You're a gentleman sir!

Lazz

[Olazz]

Just had a reply from Becker autosound LLC.

" That model radio did not need a shorting plug for the audio to work.
Sounds like your radio is defective. "


So for anyone that has that model Grand Prix hope that helps !

[scoot]

It is inconclusive whether it is the radio or amplifier.  There must be some Becker geeks in the UK...

[450sl]

wiring diagram