Grand Prix Wiring

[jeffc280sl]

Recently purchased a Grand Prix radio with separate amp.  There is an 8 pin connector on the radio which connects to the amp.  There is a connector for the antenna.  Pretty straight forward.

There is also a round 8 pin (counting the center pin) input connector on the radio.  Does anyone know which type of connector is used and the pin outs?  There is also a separate black wire coming out of the amp.  What does this wire go to?  The radio is beautiful and it is supposed to work.  Hope so!

Jeff C.
1970 280SL 4-speed

[Douglas]

I think the plug in question is an open DIN plug for an optional accessory like a cassette player.

Douglas Kim
New York, NY
280 SL #016220

[jeffc280sl]

Hi Douglas,

That would be nice to have.  Where is the power connection to the radio?

Jeff C.
1970 280SL 4-speed

[hauser]

Anyone know a source for an amp for the Grand Prix stereo?

1969 280sl 5 spd        1999 ML320          Gainesville,Fl.

[Douglas]

I'm going to let someone else answer the power connection question. Don't recall off-hand and don't have another radio handy.

Hauser, I would think you could find the amp if you contact Ed Ebel at Becker USA in NJ. Run a search on Ed's name and you'll find the info on this site. He's an excellent resource.

Jeff, you should also contact Ed. He can sell you a DIN plug adaptor that will enable you to run an ipod off your Grand Prix. It goes from the back of your head unit and rests in your glovebox. Totally stealth application for about 50 bucks. We've talked about it many times on this site.

Douglas Kim
New York, NY
280 SL #016220

[hands_aus]

Some of the Becker radios had a DIN connector for an optional Short Wave tuner.

Search for Becker, you will find lots of info on here.

Bob (Brisbane,Australia)
RHD,1967 early 250 SL, auto

[jeffc280sl]

Thanks Bob,

I have searched this site for details of the pin out and so far have not found the information.  ja17 posted what looks like the right stuff but the scan is low res and I can not read the print.  I have sent an email to Becker here in the US and hope to hear from them shortly.

Jeff C.
1970 280SL 4-speed

[jlennon3]

The amp needs to be grounded; maybe that is the black wire you're wondering about. You can confirm if is a ground wire (or not)with a continuity tester. Connect one lead of the tester to the metal case of the amp and other end to the black wire. Good luck!

[jeffc280sl]

Update on my radio situation.  Discovered the radio face plate is too small for my opening.  While advertised on Ebay as the radio for 280SLs it is designed for a 1 3/4 inch opening.  The opening in my 1970 280SL is 2 1/8 inches tall.  Contacted Becker in NJ and they suggested I send it to them for a trade in.  Did that today.  I did find out from them that the radio was made in 1964.  Inside it is crammed with tubes, electrical components and fine gear mechanisms.  The tuning bar (wonderbar) is 100 % mechanical.  It's just outstanding engineering for 1964.  I'm sure it was a very expensive option for whatever car it came from.  I'm hoping to exchange the mono 1964 Grand Prix for a newer Stereo Grand Prix that has been reconditioned by Becker.  I can not imagine a newer radio being more valuable than the one I sent to them (provided it works, also as advertised by the former owner).  It's a piece of mechanical and electrical engineering art.  The new radio should also have a din connector for an auxilliary input.  I'll try to hook up an MP3 player sometime and let the group know how it works.  Also may add a new amp provided I can hide it somewhere.  The amp that came with the 1964 radio was a 7 watt amp.

Jeff C.
1970 280SL 4-speed