I have known about a way to easily bypass/integrate into the Mustangs "premium" stereos for a while and would like to share. There are more then a few ways depending on what you want to install and what you might install later. I am installing it so that I will be able to use the new alpine decks subwoofer output to control the factory subs. I am going to bypass the factory amp for the mids and highs as it is not a ver clean amp.
Remove the radio with Ford radio removal keys, these are available at any auto parts store for a couple of bucks.
Disconnect the harness's on the back and then take out the t-15 screws that are on the bottom of the dash, below the radio hole.
Once the screws are removed you can gently pry the front of the dash of and expose the hrns's that we need to find. They are attached to the metal part of the dash right beside where the radio was. Disconnect the black hrns shown, and if you plug your factory radio back in you will now have nothing but bass.
With these two hrns's you will be able to keep the factory hrns's in the car and integrate alot more easily. The model numbers of the hrns's I used are FDO2B and FDO3B. There will be two grey rectangular harnesses that are identicle in each package. You will only need one. Wire your radios speaker output to the black rectangular hrns(the one I pointed to that was inside the dash), as well as to the smaller black hrns that was attached to the back of the radio. The small black hrns will be the subwoofer input and the grey rectangular one will be the decks speaker output for the tweeters.
If your new radio has a subwoofer output, you can do like I did and wire some RCA's to the smaller hrns. By connecting these to the sub output on the new radio, you will be able to use the decks variable sub output(if available). The factory system is use to a higher level input then most decks RCA output can supply. I bought a line driver(rca level amp) to solve this and was amazed by the output of the factory speakers from the Alpine deck.
You will be using all three hrns's either way you wire it. All there is left to do now is to adj the line driver output and slide the deck in the dash.
This easy bypass has been in Mustangs for a while. I have used it to bypass systems in older fox-body styles, although the hrns was more towards the glove compartment and a little harder to find. I do not know if this is done on the new body styles, if there is someone in the phoenix area that has a new Mustang and wants to find out I could look...
Page 2 - you just read this man...
Page 3 - Radar detector
page 4 - New wheels
Page 5 - Tail light tint
Page 6 - How to upgrade your big 3 power wires
page 7 - Sub woofer box, voltage display, dist block
page 8 - dynamatting the doors and the 6.5 speaker baffle/enclosure
page 9 - amp rack
page 10 - kick panels and doors
page 11 - The DETAILS page
page 12 - area 51
