Swapping out head unit on Ford with premium sound

Discussion in 'OT Driven' started by crashmoto, Mar 24, 2010.

  1. crashmoto

    crashmoto Eagle Scout. I don't give a fuck. OT Supporter

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    I posted this in a subforum but the response there is slow and I want to get this finished today.

    2000 Ford Windstar with factory premium sound (not mine). The head unit was a birthday present.

    I am wiring in an aftermarket head unit to the factory wiring using a scoshe wiring harness. Everything appears to be connected correctly via the harness but only get sound through the front speakers. I'm guessing that there is an amplifier for the rear channels that we need to send a turn on signal.

    I compared the scoshe harness to the factory one and there is an additional pin that is not included on the scoshe one. When I check this pin with a voltmeter with the factory radio installed, it registers in the milivolt range ~150-200. I know that the amp turn on output on the aftermarket unit is 12 volts but I am reluctant to hook that up to the extra pin location. There is also an amp ground wire coming out of the aftermarket unit.

    Any way to keep the factory amp in the new setup or is it pretty much impossible and I just need to bypass the amp?

    Aftermarket head unit is a Sony X-plod CDX-GT700HD
     
  2. Stinkypie

    Stinkypie New Member

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    Is there not an "antenna" or "amp" blue lead coming off the new radio? Wouldn't that tell the factory amp to turn on?
     
  3. crashmoto

    crashmoto Eagle Scout. I don't give a fuck. OT Supporter

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    Yes there is, but the factory radio doesn't send a 12v signal.
     
  4. upparoom

    upparoom OT Supporter

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    run a bypass wire to the factory amp to provide it 12v when the head unit is on
     
  5. Stinkypie

    Stinkypie New Member

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    I didn't read the entire first post because my question was answered in it, lol.

    We had this issue with a friend's Thunderbird, but I can't remember how we got past it.
     
  6. Stinkypie

    Stinkypie New Member

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    Maybe slap a voltage regulator on the 12v lead? I have no idea.
     
  7. crashmoto

    crashmoto Eagle Scout. I don't give a fuck. OT Supporter

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    Do you mean run a relay to supply/control power to the amp?
     
  8. Stinkypie

    Stinkypie New Member

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  9. crashmoto

    crashmoto Eagle Scout. I don't give a fuck. OT Supporter

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    I have seen people recommend bypassing the amp but I would like to avoid doing that if at all possible.
     
  10. Stinkypie

    Stinkypie New Member

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    Like which pin are you looking at?
     
  11. Stinkypie

    Stinkypie New Member

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    I'm looking at wiring diagrams but can't tell wtf I'm looking at.
     
  12. crashmoto

    crashmoto Eagle Scout. I don't give a fuck. OT Supporter

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    The connector looks kind of like the bottom one and I will recheck the pins but I do not think that the scoshe connector has the amp ground wire on it.
     
  13. guest

    guest 

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    if you wire in a resistor in the amp turn on wire, you can increase the voltage because V=IR
     
  14. Stinkypie

    Stinkypie New Member

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    Does this have the rear seat entertainment package?
     
  15. crashmoto

    crashmoto Eagle Scout. I don't give a fuck. OT Supporter

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    Unfortunately, I don't have the harness right here with me. It's at my father's place. I'm mainly concerned about what signal to send the amp to turn it on. I'm pretty sure I have it narrowed down to the right pin, just need to know whether to send it 12v (which the factory radio does not) or maybe connect the amp ground wire from the new head unit.
     
  16. crashmoto

    crashmoto Eagle Scout. I don't give a fuck. OT Supporter

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    Yes. I know it will not work with the new head unit.
     
  17. crashmoto

    crashmoto Eagle Scout. I don't give a fuck. OT Supporter

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    Thanks for your suggestions!
     
  18. Stinkypie

    Stinkypie New Member

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    I'm showing that the rear audio controller should have 12v going to it from the central junction block. This leads to me believe it's powered by something other than the radio, but, and I'm probably looking at the diagram incorrectly, it doesn't show a remote line going to the controller.
     
  19. Stinkypie

    Stinkypie New Member

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    Ok, I see now. There is power going from the radio, to the junction block, and then to the rear speaker controller. If there is a fuse in the junction block for the rear speakers, wouldn't it blow if 12v was too much power?
     
  20. crashmoto

    crashmoto Eagle Scout. I don't give a fuck. OT Supporter

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    I'm thinking that the amp ground is the switched power. I think it makes sense.
     
  21. James Deanely

    James Deanely Active Member

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    Had the same problem on a Mustang. Decided to bypass everything and run my own wires to my own speakers. Why would you want to retain the factory amp anyway? Assuming you have a decent after market head unit the sound coming from that will be just as good or better then if connected to the factory amp.
     
  22. Tommy

    Tommy Long Member Standing

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    I had to run an amp bypass cable for my 98 Contour SVT premium sound system.
     
  23. Stinkypie

    Stinkypie New Member

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    It would probably be easier just to run your own speaker wires. That's what I did in my ford van.
     
  24. crashmoto

    crashmoto Eagle Scout. I don't give a fuck. OT Supporter

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    Yeah, that's plan B. I'll try the ground idea and if that doesn't work I'll bypass.
     
  25. VolksDragon

    VolksDragon New Member

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    +1 on the bypass. Find the amp location and run new lines to the vicinity of the amp output so you can power all the stock speakers directly without having to run new lines all over the place.
     

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