Problem with 2000 stereo wiring

Discussion in 'Mustang Sound & Shine All' started by adamd303, Nov 2, 2007.

  1. Hey guys (and gals), I searched the archives, but couldn't find any mention of this problem, so I'm hoping somebody knows what's going on...

    My mustang:

    No mach system
    Factory split head units receiver/cassette and CD

    Here's my dilemma...sorry if this is long but I figure the more info I give the easier it will be for somebody to identify where I screwed up here...

    About a week ago, I turned on my car, and then tried to turn on the radio. It made some low growling kind of noise and then turned off. It wouldn't turn back on since. I first checked the fuses under the dash and they all were fine.

    Assuming it was a problem with the head unit, I presumed the head unit had blown out and decided to attempt to replace it. (I was going to replace the head unit eventually, anyway.) I removed the two units from the dash without much problem. I've installed aftermarket stereos before so I didn't think it would be a problem. I had the wiring diagrams, and having spliced wiring before, I was prepared to do that again. If I didn't feel comfortable, I also planned to pick up the harness.

    When I looked at all of the connections, I realized none of it matched any of the diagrams I had. Upon further research at that point, I discovered that there is a separate amp under the dash. The connections I had break down like this:

    CD player:

    horizontal 5 wire connector--I believe these are the power cables
    Black 6 prong rectangular connector attached to a gray cable
    Black ground wire

    Head unit:
    Antenna plug
    horizontal grey 8 plug connector--I believe these are the power cables for the head unit
    Black ground wire
    Black 6 prong rectangular connector attached to a grey cable
    Black 8 prong rectangular connector attached to a grey cable

    Assuming the last one would have the speaker wires bundled together, I stripped a small portion of the grey insulation. Instead I found bare wires. I patched it up, and bought a harness that attached to the two 8 prong connectors. I plugged them in and spliced the wires to the head unit's harness. I also ground the black ground wire.

    At this point the new head unit powers up fine, but there is no sound coming from any of the speakers.

    Any ideas???
  2. Is the old amplifier still in the circuit or does the harness bypass the amp and connect the head unit to the speakers directly?
  3. IIRC, you need to disconnect the two harnesses from the factory amp and attach those to the new stereo harness. They'll have the same plugs on them as the ones that come out of the amp, but you need to bypass it. It should be the same stereo wiring harness as my 95 and that's what I had to do to get away from the Mach 460 when I eliminated it.
  4. The harness connects into the factory amp. Although, it doesn't really make sense to me when we stripped some of the insulation off the bundle the harness connects to didn't have separate wires, it looks like the inside of a power cable for an amp.

    I found the harness to bypass the amp where all the diagrams I had said it should be but there were 5 wires connected to that harness, instead of the 8 I would have expected, so I didn't try to bypass.
  5. So there are another set of harnesses hidden under the dash?? Any idea where I'm going to find these?
  6. It's been years since I put my aftermarket stereo in, but I believe they were down on the right side of the factory amp. I think I was able to reach in through the CD player opening to disconnect them.
  7. If you don't do the amp bypass you can simply hook up the remote turn on lead (blue /white) from the new head unit to the blue/white on the rectangular harness that plugs into the car. This will turn the factory amp on so you should have sound. The only negative to doing this will be that the volume will be quite sesitive and if the head unit beeps when you press the buttons it will be awfully loud. If you already tried this and still have no sound then you most likely have a bad factory amp and will need to do the amp bypass.