i would be looking for either a bad connection or incompatible wiring

 

If they used an adapter harness I would check to make sure they wired it properly.

 

I've tried 3 different harnesses, it's not the harness.

 

Pull the stereo out and look at the wires going to the plug for the truck side. Make sure all the terminals are pushed in deep enough to make contact. Then look at the plug from the stereo side and make sure they are all pushed in far enough to make good connection. If they are all making connection then the only other problem is the Speaker positives and negatives are not wired properly. Trace the wires from the speakers to the plugs and make sure they are neg. To neg. And pos. To pos. On the front speakers. Some stereos are real picky about that as others are not. If they are all correct take your head unit out get your money back and get a new head unit some where else.

 

Like I said in past post, run speaker wires DIRECTLY from head unit to speakers. DO NOT USE THE FACTORY WIRING ON NEW HIGH POWERED RAIDOS/AMPS. Ford used a common ground on their audio systems, MOST new radios require a FLOATING ground and will not operate with factory wiring!

I have repaired many car radios just for that reason!!

By the way, 17 year old speakers.... REPLACE THEM!! Or toast your radio.....

 

What is a floating ground.
Floating Ground System*Doesn't really mean "floating" at all, just that the speaker outputs are*NOT*common with ground. This is the type that have a "+" an "-" .
In layman's terms two wires per speaker. I can't remember the last time I have seen a speaker ground itself to the vehicle. This truck should have two wires per speaker a positive and a negative.

 

correct. 8 speaker wires out of the radio to the 4 speakers.
i have installed hundreds of high powered stereos in vehicles over the years, and no once did i ever have to run separate speaker wires, unless there were no speakers there to start with like in the 60's and early 70's cars..

 

That's what I was thinking, I think when I did the stereo in my 69 Chevy it had two wires per speaker as well. I've never heard of the term floating ground until today.

 

the older cars had them, especially the cars with single speaker am radio systems.

 

I can see the car manufacturers doing that back then low watt systems that would work fine until the door Hing pins started wearing out lol.

 

Then either the "adapter" harness or the aftermarket head unit is screwed up

 

Brad, did Ford ever use JBL custom amplifiers in our trucks? I came across a crew cab in the junkyard a while back and it had a JBL amp behind the rear seat, and it was in no way a regular aftermarket amp, it had to be something that was custom made for an auto manufacturer.

 

Not in these truck. I know in the later Mustangs they used BOSS equipment

 

I think JBL did have something to do with the premium sound though. JBL was mentioned in the owners manual for our 94 explorer, it has a combination factory sub/amplifier, but a cassette deck though.

 

My mom's 94 had the JBL sub in it. It was in the back cargo area but it had a factory cd player it was an Eddie Bauer edition.the amp in my truck is behind the rear mounted to the back of the cab on the drivers side and the speaker box is mounted to the the rear wall on the passenger side. Just for clarification it is not a factory amp. But it's about the only place to mount an amp that's out of the way.