I still havent got my car back from the shop. It has been in the shop for almost 2 weeks. So I cant look at the wiring. But I have my wiring harness to connect to the factory harness (it is two pieces, one gray and one black, both thin), and my new head unit. I have looked at wiring diagrams, and have a few questions. Again, I have an 89 gt convt with 6 speakers.
1. First, the HU harness, do I need to connect blue/white amp wire? 2. Secondly, do I need to connect the red and yelow together, or keep them seperate? 3. There are 3 orange wires on my wiring harness that plugs into the factory harness. So, the HU harness wires has an obvious orange/white illumination. The other harness that goes into the factory has 3 orange. It has orange/black says dimmer ground, it has an orange that says illumination dash, it has a orange/white that says dimmer. Which one of the orange wires do I connect to my HU orange/white wire? You would think the orange/white that says dimmer, just to match the color. But the diagram I have says do not use this wire. So do I use the orange, and connect it to the orange/white hu illumination wire? 4. Lastly, HU has 4 sets of speakers wires, how do I wire this since my car has 6?
Again, I dont have my car, and even if I did I might still be lost. I am trying to figure this out, and get all the wiring together I can before I get into the car. Please help me someone
the 89's can be a little tricky with wiring as they can have a common ground amp built in. 95% of aftermarket radios use a floating ground system and these to do not mix well at all and can result in blown equipment or bad sound. Do the hrns's (black and grey) look like they are the same shape, just different colors? If this is the case there is no amp. If there is, the amp is normally located inside the bottom of the dash. It is metal, hex-shaped piece with a bunch of holes in it. Can you see anything like this?
1.) If there is an amp in the car we will need to bypass it, Luckily it is easy to do on that year, really easy... 2.) No, wire them seperatly or the deck will run with the key off. 3.) The dimmer wire will have no voltage with the lights off, and will vary between 8-14v with the lights on, depending on how bright the dash lighting is. It is not the one labeled ground. 4.) The front speaker should be wired together. You can add a cap as a high pass filter, to block the Bass from the smaller one. This will give better sound quality
Ok, My car has an amp. First off, the wiring for the stereo and speakers when i got the car was jacked, no wondering nothing worked. It has 2 sets of wires and 2 connectors coming out of it. Only one of them, the one with the red wire was plugged in, there was nothing in the other hole. I have the speakers wired. I need help with the rest of it. Can someone please tell me what to do. I have no clue. I have the one plug connecting to one of the amps. Then I have 2 connectors, that look to plug in the back of a stock radio. None of the colors seem to match up with anything I can find.
Bypassing the amp completely is fine, i want my aftermarket headunit and speakers to work. Can someone please help me out. I am lost. I have connected 25 aftermarket headunits, just nothing like this. Part of the problem is that it was a mess before I got it. Please help me guys. Thanks, Landon.
Posts: 206
Joined: 3/28/2003 From: United States Status: offline
there is a bypass harness inside the dash radio opening. I beleive off to the side. Look in there with a flashlight. I looks like two of the black radio harnesses plugged into each other. Unplug them and use that as the speaker harness. Find your factory amp and just unplug all the connectors. Then interface into the new black speaker plug and the factory grey plug in the dash with a wireharness for the new radio.
Posts: 182
Joined: 8/25/2004 From: Virginia Status: offline
I would use the wireing harness and plug it into the factory wireing.
Then from there wire up connections such as ground, ignition, 12v power to the aftermarket head unit Wireing harness.
After that instead of messing with any amp bypass connections I would run new speaker wire and wire it directly to my After Market HU wireing harness. Tieing the dash and door Speakers together at the HU. But with that being done you will want to install "Bass Blockers" on the dash speakers so you will not blow them.
to answer your previous questions....
1) You only need to Blue/White wire if you are installing an aftermarket amp or it can even be used for a motorized ant. But its not needed if you are not planning on installing an Aftermarket Amp.
2) What i am getting here is your asking about the red and yellow on your wireing harness to your HU harness. If I remember correctly , been a long time, the yellow is your 12v constant power and the red is for your ignition or vise versa do not connect them together or get them switched unless you wanna get a jump start every time you want to drive your car.
3) There aregoing to be wires that don't get connected. They may be for dimmer setting s that your New HU doesn't have or even to the amp I cannot be for certain without looking at it first hand.
4) Answered in paragraph up top.
Please feel free to explore other directions. This is just what I would do, not that I am an expert. You may have a little more fun this way. Although getting the speaker wire into the door can be a pain. I just use an old wire hanger to help feed it through.
And no laughing at my drawing. HAHA it sucks soo bad.
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1989 MUSTANG RADIO WIRING INSTALL HELP PLEASE - 
