About a week ago I posted a question about stero installation. I never did get an answer but today I figured it out for myself, so I just wanted to post what I found out JIC anyone else had the same question.

What I tried to do was install an aftermarket cd player myself. I bought the wiring harness and the plastic kit that takes up the extra space.

After I spliced all the wires together and pluged everything together and grounded the stero, I would get power to the deck but I would have no sound.

The problem I figured out was that the harness did not come with a power wire for the stock amps. So to fix this I cut the white connector off of the amp power wire and got a connector so I could run both the amp power wire and the deck power wire together so they would both get power from the same sorce.

When I searched on this subject, some people said that the only way to do the install was to bypass the amps all together. BUT THIS IS NOT TRUE. You just have to power them.

BTW, there are three stock amps at least in my car. 1987 GXL. There is an amp in the front passanger speaker, (not in the speaker, but in the black rectangular box that the speaker is in), and there are two more in the rear, one in each tower where the speaker is.

I hope this can help someone.

Tim

 

Also there was something else that I found out.

In the stock radio, when I took it out, there seemed to be two antenna cables being pluged in to the radio. One male and one female. I thought this was wierd because I thought I only had one antenna. I was wrong again. When I was looking through the FSM on www.FC3S.org, I found out that there is two antennas. There is the one noticable electric antenna in the rear, and there is also one on the front windshield.

So if anyone ever wondered what those two black thin lines on there windshield were, no you know.

BTW, the male cable that goes into the stero is for the rear antenna, and the female cable that goes into the stero is for the front windshield antenna.

Tim

 

You will want to bypass the factory amos if your aftermarket radio has more than 20 watts a channel

The stock amps in a GXL are designed for a 6-7watt RMS input with a peak input of 15 watts. Putting more than that will either:

Burn out the output of the aftermarket radio

Burn out the input to the stock amps

blow up the speaker(s) by radically over driving it with huge amounts of distortion.

This has been covered over and over BTW. I am sure that know one answerd simply because they figured everyone anyone would search.

 

They are for the factory radio FM diversty system. The reversed lead is for the windsheild antenna found on the GXL, GTU and Turbo and convertible models

 

And again as covered countless times (I don't know how many times I have posted the wiring both in diagrams and typed words for the wiring of an aftermarket radio)...

So again:

The factory amp turn on lead (blue/white) connects to the amp turn on lead of the aftermarket radio, (which [surprise surprise] is also blue/white on 90% of the brands out there) not to accessory (as the radio is powered).

 

Funny how nearly all problems with aftermarket stereo installs in FC's revolve around the stock amps. Despite the fact these 15+yo dinosaurs put out less power than even cheap aftermarket head units, people still what to run through them instead of doing the sensible (and much simpler) thing and running all new speaker wires to bypass them and any other problems entirely. It's just so easy!

Wiring adaptor harnesses are another thing that confuse me. My aftermarket head unit was incredibly easy to wire up to the stock stereo wiring (minus the speakers of course) with nothing more than a few crimp-on terminals and a relay to make the antenna work. So what to these harnesse even do? Waste of money.

A note about the stock twin antennas, as I understand the way radio signals work there's no point in wiring them both up to an aftermarket head unit because quite sophisticated processing is required to make it all work. The stock head unit used which ever signal was strongest, not both at the same time. Something about the two antennas having to be exactly the same distance from the source to make any improvement to the signal, which would only happen if you're driving exactly perpendicular to the direction of the source. I read an article about this in a mag recently which explained all the technical reasons why, but the short version is it doesn't work so don't bother.

 

May I ask, why is the 2nd antenna in the windshield needed? I am having my windshield replaced soon, and I guess the insurance people will ask if it has one or not??? thanks

 

I just straight bypassed them and I now have a 500 wt amp running 4, 41/2 inch speakers.

 

it is used for the factory diversity radio. If you no longer have a factory radio then you can probably not use a windshield without one (although I think all the factory tinted bar windshields had the antenna).

98% of the aftermarket radios do not use diversity tuning.

 

The factory stereo is crap.&nbsp The factory wiring is crap.&nbsp If youre going to do it right, you redo ALL the wiring yourself and ignore the stock wiring.&nbsp Anyone who has put in a high-end car audio system will/should do this in the first place.&nbsp I'm not a real big fan of "harness adapters" for the FC - all of them have their problems.&nbsp The stock speakers are a waste of time, as is the crappy stock amplifiers.&nbsp Do yourself a favor and run your own aftermarket speakers and amps...


-Ted

 

Yeah, and that is why someone needs to buy mine!!

 

Definitely the speaker wires, but the rest are fine. The battery, accessory and illumination wires on your head unit plug straight into the factory harness, and the antenna wire just needs a relay to let it plug in too. There's no ground on the factory harness because the stock head unit is grounded through its bracket, but most head units come with a terminated ground wire anyway. Too easy.

 

hey, has anybody tried connecting the aftermarket radio to the windsheild antenna... does this work? do you get good reception... cuz my antenna has started clicking a bit when i had the stock head in, and since i didnt have a relay handy to reverse the polarity of the power antenna wire i never bothered hooking up am/fm (dont really need it with the mp3 player... but still it would be nice to have), I'm wondering if anyone has had any success getting a male to male wire to use the dash antennas?

Besides the fact that i think it looks better with the antenna down, it also makes an annoying wind buzz on the highway with the top down...

Oh, and as far as running with the stock amps and speakers... definately upgrade the speakers and either use an aftermarket amp or the headunit amp... definately will sound better than what your car has stock... no speaker in a car is gonna stand up well after more than 10 years... and amp tech has gotten alot better, so may as well take advantage of it (only thing thats a little bit of a bitch is running speaker wire thru the door wiring channels :p) but definately worth it in the end. just my 2 cents

 

The drawback to using a factory windsheild antenna is that for best FM reception in North America you would want an antenna 31.5 inches tall. The windshield antenna is not that tall (and neither are the rubber break proof antennas that some people like).

Furthermore for best AM reception you want the tallest antenna possible.

The windsheild antenna really should only be used with a diversity system that can utilize the different lengths and angles of the antennas.

 

Baseball fan eh.