Best way to bypass the stock "Premium Audio" system?

[Auxient]

I have a very clean (1 owner) 1987 Grand Marquis and I decided that I would like to be able to listen to my own music in it and found, much to my frustration, that the wiring is a mess. There are 3 connectors instead of the usual 2 and one of the connectors loops into itself. I tried hooking up just using the 2 connectors and got power but no sound and I am pretty sure that I fried the stock football shaped amp in the process. I put the stock stereo back in and hooked it back up exactly as it was and I still have no sound. Is there an easy way to bypass the amp short of cutting wires and running new speaker wire? This car is MINT and I would like to keep as much of it unmodified as possible.

[sly]

Have you tried disconnecting the loop and using that connector for the speakers instead of the other one?

[gadget73]

Lets start with the stock wiring diagram so you can compare what you've got to what you ought to have. See attachment for that.

The football is pretty tough, but even if it died it only runs the front speakers. The rear speakers run straight off the radio so even if the amp died, you'd have rear speaker life. If you have no sound at all, you may have killed the radio. Has it ever worked, or did you get the car with the stereo not working? Not uncommon for people to do a bodge job installing an aftermarket stereo, or in removing one and leave stuff not working. The wiring was a complete CF in my 84 Continental when I got it, but re-connecting all the stuff back to stock made it work again.

anyway, if you're looking to put in an aftermarket stereo, the rear speakers already have wires from front to back that are compatible. The front speakers are the issue. The stock speakers do feed through a connector, C1118 that is located in the passenger side kick panel area. If you get wires from the stereo to that point, it will feed the door and dash speakers without any further fuss. Not sure which connector it is in there, you'll have to compare the wire colors.

[Auxient]

Lets start with the stock wiring diagram so you can compare what you've got to what you ought to have. See attachment for that.

The football is pretty tough, but even if it died it only runs the front speakers. The rear speakers run straight off the radio so even if the amp died, you'd have rear speaker life. If you have no sound at all, you may have killed the radio. Has it ever worked, or did you get the car with the stereo not working? Not uncommon for people to do a bodge job installing an aftermarket stereo, or in removing one and leave stuff not working. The wiring was a complete CF in my 84 Continental when I got it, but re-connecting all the stuff back to stock made it work again.

anyway, if you're looking to put in an aftermarket stereo, the rear speakers already have wires from front to back that are compatible. The front speakers are the issue. The stock speakers do feed through a connector, C1118 that is located in the passenger side kick panel area. If you get wires from the stereo to that point, it will feed the door and dash speakers without any further fuss. Not sure which connector it is in there, you'll have to compare the wire colors.

Thank you for that diagram. I have 3 connectors when I remove the radio. One is obviously power, one has 5 wires running to it and the other one is attached the the rear of the radio and seems to make a loop and plug into itself partly. It also has a red wire that attaches to the back of the radio with a nut. I believe I have the "common ground" setup. Now, when I tried my aftermarket stereo, I plugged my black connector to power and the grey one to the 5 wire connector on the left. I will attach photos for reference. I got power but no sound from any speakers. So, noticed the odd wiring and connectors and put the old stereo back in exactly as it was before. Same deal. Power but no sound from any speakers.

[gadget73]

Did the stock radio ever work ?

[sly]

If this is the same person as on FB, their car uses 5-wires in the 8-pin speaker harness, the 5-wire power harness, and the "loop" is another 8-pin plug like what plugs into the radio, but is plugged into another 8-pin harness. Had to blow up the pic on my PC from FB to see the wires individually. On my phone it looks like the 8-wire setup. I'm not sure the aftermarket radio will survive being plugged into that harness or if only one speaker would end up working.

Here's the pic.

[turbo2256b]

when i installed my aftermarket radio in my 87 that had premium sound ran all new wires. No body made an adapter set up for the premium set up. the front speakers in the doors and dash i ran in series. ditched the factory amp.

[gadget73]

I dont know what the loop is about. Unless thats the point where the premium sound output meets the front speaker connections. The wire colors do not look right though.

The rear speakers already have proper wiring.
right rear + is pink/light blue stripes
right rear - is dark green / orange dots

left rear + is pink/light blue dots
left rear - is pink / light green stripes

The front is a common ground to the amp, but with a little creativity you can make that work. The amp will have to lose it's plugs and you'll need to couple some things together with the pigtails.

At the radio
front right + goes to light green
front right - goes to black/white dashes
front left + goes to white/red
front left - goes to orange / light blue dots

At the amp connectors

light green goes to white / light green dashes
black / white dash goes to dark green / orange
white / red goes to orange / light green dashes
orange / light blue dots goes to light blue / white dashes


basically what we're doing here is using the 3 original input wires, plus the logic mute wire to get the four wires to the front speaker without modding anything in the car harness. We're hacking up a premium sound amp but thats not exactly the end of the world.

of course this assumes its the 2 channel setup that Alldata gives as the only option. If its the 4 channel football there aren't going to be enough wires to get this done.