Dont know

[chadomac]

had after market radio in it...radio worked pulled it out put another aftermarket radio in now can barley hear sound when radio is turned all the way up any ideas?

[chris91]

If it has the harness with the green plug make sure none of the pins have come loose at the plug. Ive had two of them now push a pin loose when I plugged them into the factory harness. It did the same thing as you're describing too. You could barely hear it with it cranked.

[chadomac]

forgot it is a fox.....no green plug got a gray and a black

[redfirepearlgt]

If you haven't put the old unit back in (assume it works) and see if everything is okay. If all works,then ...

What kind of radio chad?
1. Some higher end radios came as preamp unit only (no amplified outputs). Are you running aftermarket amps?
2. If no amps and the unit is used it may also have blown FETS and need to be repaired.
3. If speakers are wired out of phase this will often times cause a great reduction in sound. One is pushing while the other is pulling and they offset each other. This highs will be there but the mids and lows will be virtually unheard.

Chad

PS - Missed seeing you guys at the cruise in.

[chadomac]

Hey chad it is a alpine head unit , i am not running any amps. i can hook a external speaker up and it works great it is just the ones in the car. i unhooked all the speakers and started re hooking them up all i have to do is hook up the pos side of the speaker no ground and i get sound you can barley hear it and its like that on all speakers.

[redfirepearlgt]

Hey chad it is a alpine head unit , i am not running any amps. i can hook a external speaker up and it works great it is just the ones in the car. i unhooked all the speakers and started re hooking them up all i have to do is hook up the pos side of the speaker no ground and i get sound you can barley hear it and its like that on all speakers.

R U replacing the factory unit and did the factory unit work before you removed it on all 4 speaker channels? If this is the case, I am going to guess that your year of mustang may have what's called a floating ground stereo which will not work on the alpine unit without some mods. Floating ground refers to the fact the each speaker has only a hot wire running to it then each negative wire is grounded to the chassis. Look to the back of the speakers to see if one of the terminals runs to chassis ground vice going all the way back to the head unit. Rear speakers will likely be the easiest to see this on. THe head unit is also grounded which completes the path for the circuit. THe Alpine unit uses common ground meaning that each speaker has two wires, a pos and a neg. If this is the case you will have to rewire the speakers and pull positive and negative wires back to the head unit to isolate teh speakers negative from the head unti negative. As it stands (if this is the case) you are "floating" the output signal form each speaker back to the head unit via the headunit's power ground which can and will cause damage to the alpine unit due to imepdance mismatch. Some radios do have an option on them to convert them to floating ground as well. Check the Alpine user/install guide for this which could save you a lot of wire pulling. Usually involves a switch located on the back of head unit for cars with such a wiring system in which you wish to reuse the existing speaker system with an updated head unit. Let me know if this is the case and how it works out. Chad.

PS How's JR???

[chris91]

forgot it is a fox.....no green plug got a gray and a black

Ah ok, yeah all the SN's and Lincolns Ive been messing with lately have the green plug for the speaker wires. Id still double check the aftermarket harness. Those pins seem to come loose awfully easy.

[chadomac]

it appears that the car has the "premium" sound system with the 6 speaker set up and a factory amp. would the amp make this do this?

[redfirepearlgt]

it appears that the car has the "premium" sound system with the 6 speaker set up and a factory amp. would the amp make this do this?

Does the old head unit still make the system come to life properly? If yes, then you will need to find the proper adapter kit to integrate your alpine unit into the existing premium sound system or revisit the wiring. BTW what model of alpine unit? If the answer is NO, then you need to decide on how much money you wish to spend in upgrading this system, because something is clearly bad. This will include at minimum pulling new wires for four speakers and changing the speakers as well. The facotry speakers will VERY LIKELY not have the proper impedance to match to the speaker outputs on the alpine unit and will likely burn the unit up if you should attempt to wire directly to them bypassing the amplifier in question.

It all boils down to that BIG QUESTION. Does the system work in he car with the original head unit back in place? Yes or No. Once this has been verified we will then know what direction to take in getting the alpine unit to work.

Chad