Putting in a radio, have some questions

[JESSEGG]

Hey Guys,

The people I bought this 86 944 from gave me a brand new radio (because the original was gone) to install. It is a real nice Dual AM/FM CD Reciever with a front panel aux input, USB charging post and detachable face plate. It has no problem fitting in.

I have it all ready to go an terminate to the wiring harness. I believe I have narrowed down the right wiring harness because I pulled out one of the door speakers to determine which wires were the speaker wires and they seem to be in the same bundle as the rest of what "appears" through common sense to be the radio wiring (please note image).



In this image you can see a yellow, red, black wiring (the others are the speakers). The new radio has a red wire (accessory-ignition circuit or switched 12 volt source) a yellow wire ( memory - battery circuit or constant 12 volt source with an inline fuse) and a black (ground). The antenna is self explanatory.

Am I on the right track? I want to install this tomorrow but I am worried about doing it wrong. Is this something one of you guys have done? Please advise.

There are to other loose phantom wiring harnesses down there too, I just dont want to blow something up.

Thanks,

Jesse

[Guest765]

Worst case you'll blow a fuse or two. I did. I believe if I remember right that you'll want to use the black as ground, because that black wire actually powers the preamp for the antenna signal. Technically wiring it in series like that will provide +12v to the preamp and at the same time eliminate the possibility of a ground loop because you're making both a common ground at that point.

If you've never heard a ground loop its a whistling sound thru your speakers that changes with engine rpm, extremely annoying.

You'll need a multimeter to check which is switched and which is constant power for memory etc. Unless you want to just use process of elimination which works too.

Either way you don't need to worry about blowing anything up, power is isolated in its own wire (I think it was brown? I don't remember its been a while) and the speaker wires are one either end of the connector that goes to your fader knob. Its easiest to just eliminate the fader knob, its probably worn and will cause bad sound quality anyway.

[Thekidwitha944]

Good times, I went through ttying to do it myself with no help (bad idea) and many fuses lost their lifes to my stupidity XD. I installed a newer Blaupunkt into my car. Trail and error is a good friend of mine. Good luck!

[Grandad#3]

Check out the link below for one of the most comprehensive radio installs.

Stereo Installation Help [86/944]

Cheers,
Larry

[porschetub]

You need to go to constant power from fusebox and keyed ignition power and an earth most likely brown,you can find a good body earth somewhere.
So you would look @ on your deck, red to power constant ,yellow to keyed power and black to earth ,blue is normally for power out of the deck for amp power or built in antena amplifier and there are others ,after that your multimeter is your friend.

[JESSEGG]

Well I figured out that the 1st image I posted was a gang harness for the speakers (yup, the red and yellow wires).

So now since I have that piece of it out of the way, I have to figure out the abortion case that the rest of this mess is. The multimeter advice is awesome, I think I am going to get moving on that to help me find the hot constant and ignition power.

Thanks for the lead on that post Grandad#3, by looking at it I think I ID'd the gang that was for the factory preamp. The last harness is a complete mess, how any of it is hot wires has me real concerned the way they are just floating under the dash.

Should I be adding a preamp? I mean is bypassing it a good idea?

Thanks,

Jesse

[mytrplseven]

normally, red for 12v, yellow for dimmer, black or green for ground, blue for power antenna.

[Grandad#3]

Hi Jesse, I found another old post on radio install.

My stereo install (with pictures) - Rennlist Discussion Forums

Cheers,
Larry

[JESSEGG]

Thanks for the advice everybody. Got the multimeter, googled how to work it for installing a radio and how to find constant power. Sifted through the mess of wires the previous owner left "unmarked" and now I have a working radio coming through all four speakers that sounds awesome.

Appreciate everything,

Jesse