I have been trying to install an aftermarket head unit in my 2003 Gt with Mach 460 system. I have tried all brands of harnesses that include an amp harness (metra, Schosce, etc.) and none of these fit the stock harnesses the look as they would fit but they do not. does any one know if there is a adapter out there if so who makes it and where do i get it. I have heard that the Mach systems were made very sophisticated and put out 8 ohms to the speakers instead of the usual 4 ohms and to put an aftermarket system in the car would be to replace the speakers amps and rewire the whole sytem is this true???? Im at my witts end and am about to throw in the towel on this and just keep the stock system.

 

no you do not have to switch everything out. You are correct on the woofer impedence but it is not an issue unless you try to replace the speakers with out replacing the deck. There was a switch of hrn's around that time and I am not sure which one you have. Pg2 of my cardomain page shows how the old style hrns's look like and if yours look like that then I can help you.

 

ttocs the harness in your page is similiar to the first one i tried i bought both the metra and scoche brands and neither one worked mine has the amp plug and one larger rectangle plug and one smaller rectangle plug ill take a pic and post it up.

If anyone can help or has any information please let me know.

 

the best thing to do, is to take the radio out of your dash and then look at the back of it. The hrns you need will look EXACTLY like the hrns that is mounted inside the radio. IF you were to take this to a local audio shop they could match one up with no issues.

 

and not all of the plugs will always be used.

 

bump. anyone?

 

if it looks similar to mine then it should be the old style, Scosche uses FDO2B and metra 70-1770. If you tried them, and they looked like they should fit but didn't then it sounds like you might have had them backwards. The power and speaker harnes look VERY similar(other then one being black the other grey) as they are almost the same shape but will not plug into one another.

 

hey ttocs they werent backwards i tried them all ways it seems like the plugs on mine were slightly larger than the harness plugs, as they were the same size as the harnesses that i bought.

 

read that 3 times(with my eyes squinting), but I am still going to need someone to translate it.

What did that mean in english?

 

basically the plugs in my car are the same size as the harnesses i bought so i need one that is slightly larger than the ones i already bought