How test 1432 System

[Maui]

Three years ago I sent my radio and amplifier from my 1992 500E to Becker to have them freshened up and to install a ear phone jack so I could play my iTunes from my phone through the radio. BTW, they were working when I sent them in but I wanted them to be like new. When I installed the rebuilt head and amp they would not work. I fiddled with them for a couple weeks and sent them back to Becker. They did something, I suppose, and sent them back. When I installed them this time the radio would light up, accept a cassette tape and the antenna would go up but after about five seconds the tape would spit out without making a sound and the radio would turn off. The radio does not even ask for code it just lights up for a few seconds, spits out the cassette and turns off. At the time I became very frustrated that I had spent several hundred dollars and at least a couple months dealing with Becker I decided it wasn't worth my time pursueing it. So, for three years I have had no working radio.

What I would like to know is where can I find a schematic of the wiring between the head unit and the amp and how can I test the connections? Becker had told me the radio worked on their bench, but I could not get it work in the car. Incidentally, I purchased a used head unit afterward from a member here and it did work but made a terrible thumping sound through the speakers every time it was turned on and had a lot of static. It wasn't a good option. I'd really like to get the stock system working. Appreciate any advice.

 

[gsxr]

Ken,

There are some basic schematics of the 1432 two-piece system in the ETM. See PDF page 95 (printed page 131/6) for the head unit, tuner/amp, and antenna. PDF page 101 (printed page 133/1) shows the fader & speaker wiring.

For testing, I don't know what you could do except make sure each end of the wiring has continuity, meaning there's no damage to the connecting cables. And confirming power/ground appears where expected.

Link to ETM (74MB download): http://www.w124-zone.com/downloads/MB CD/W124/w124CD1/Program/ETM/ETM.pdf

 

[Maui]

Unfortunately I can't test the 1432 radio in my other E500 because it's a 1994.

 

[northNH]

I have a fully functional 1432 with changer in my coupe (and sounds perfectly acceptable BTW with front Rainbows);
If it's the best you can come up with, send me the HU and I'll plug 'er in there and see what's up...

Your HU acts like mine when it's below 0° and the car has slept outside.

 

[Trae]

Ken,

My Renntech has been doing the same thing for years. . . Becker told me it is the amplifier, but I have not sent the head unit and amp To Becker yet.

Been listening to the sweet Renntech exhaust, but the wife wants music.

Based on your report, I will continue to wait. Keep us posted.