My 928 S4 came with an amp, subwoofer and all the other goodies. The receiver is ok but older. I have very bad reception on the radio. I pulled it to check the antenna. I have the shark fin on the roof and there's an antenna in the windshield. I'm not sure which one goes to the radio.
My questions:
1. Where is the antenna amplifier located.
2. There is a small black wire incased with the antenna that has a spade end on it not connected to anything. Shouldn't it be connected to something?
3. The system has a wine that goes up and down with the engine. I purchased a noise suppressor but where should I install it in the power supply?
Thanks for any advice,
Mitch

 

The wire in the antenna lead is for 12VDC power for the antenna amp. Follow the antenna wire to locate the amp. Sounds like you have a ground loop picking up RF interference from the alternator. Best way to eliminate it is ensure all the audio components are grounded at the same location.

Mike

 

On my RHD '87 S4, the antenna amplifier is just below the bottom right corner of the windscreen - there's a small lead from the windshield which plugs into a round connector just below the cowl panel the wiper arms protrude through.

Pretty sure LHD and RHD use the same windshield part no., which means on your car, the antenna amplifier is in the same corner, behind your glovebox.

 

Is that "small black wire" running alongside the antenna coax?

If so, it's likely the power feed for the antenna amp.

If you have a "power antenna" or "amp turn on" output on your head unit, use that to power the amp.

At least that's what I did.

 

If you are hooked up to the windshield antenna, poor reception is normal., but as for the whine, probably a ground issue.

 

Unamplified, yes. Poor reception.

But with the amp hooked up and working, the reception in my 928 is the best of all the vehicles I have, and probably the best of any I've owned.

 

pic of antenna amp and plug for the screen antenna to plug into which is behind the wiper spindle panel on LHD passenger side

 

You could always do what the Aus market did and drill a hole in the left rear quarter panel and mount a retractable antenna as all 928's have the aux cable in place from the factory last I knew.

But yes, that black wire is the power wire to the antenna, hook it up to the auto antenna wire and or replace the amp that the wire goes to.

 

Not on an S4...

Alan

 

Thanks for the replies.
After reading them and further research, I am going to follow the antenna wire back and find if that wire is for the power.
h2pmr Thanks for the pictures. They are always very helpful.

I also found this on here.

https://rennlist.com/forums/928-foru...-question.html