Audio Systems: Radio Issues, line level signal, external amplifier

Question
Last night my radio stopped working properly in my 1993 Ford Explorer. When I turn the volume all the way up all I get it a slight static sound and partial station reception. I can barely hear it even when I put my ear up to the speakers on full volume. It occured as I was driving and right before it stopped working properly I heard a few "popping" noises coming from the passenger front side of my truck. I partially got the radio out and checked the wires in the back and they seem to be all snug. The antenna itself is fine as well. What else could this be? ANY HELP APPRECIATED - and please be detailed as I am a first time Explorer owner.

Ok....so, in the morning when I start my truck up the radio will sometimes work but AS SOON AS I turn the lever to put on the AC or HEAT the radio shuts off.  Or, in the morning I can go out there and turn the key on accessories and it will work (sometimes) and once I start the truck up it stops working.  What the heck is going on?..haha.

Should I see if the stock amplifier is in working condition?  But I'm not sure how to specifically get to it.  Please let me know any other ideas.

Jeff
jeff@wkfrontier.com

Answer
Sounds like you have one of the hardest problems on the globe to diagnose, isolate and deal with.... (an intermittent one), especially for untrained hands. These types of problems will surface in older vehicles due to wiring fatigue and corrosion (among other things).

This could be simply a shorted speaker wire (passenger door hinge area is one place to start looking, though the short could be anywhere along the speaker wires).

If that system is a JBL factory system, it should have an external amplifier. The '93 Explorers I have worked on where NOT JBL systems, so I cannot tell you where it would be mounted, if it is a JBL system.
At any rate, if it has the JBL system, you need to check the speaker wires as well as the line level signal the deck sends to the amplifier.

You may be able to replace the speaker wiring and fix this problem.

IF that truck has an airbag..it would be better to have a professional shop do this work, as probing wires in such a vehicle can trigger the air bags causing INJURY or DEATH (not to mention they cost about 500.00 to repack!).
Additionaly, any wiring they work on would be guaranteed for the life of the truck.

Lastly, that is an 11 year old system in a mobile vehicle, it may be 'time for a new timex' (stereo-wise).  Yes, there are costs involved, but there is also peace of mind and a new warranty on the system and its wiring.

If this does not help you, you may want to try another volunteer like Mr Clark. He may be able to guide you through this more effectively than I, since I usually replace JBL systems instead of repair them. All of my customers have opted to replace aged JBL systems and this 'OEM replacing' is even less of a dollar factor if it is NOT a JBL system w/amp.

I hope this sheds some light on the matter for you.
Good luck and thanks for the question.

Sincerely,
Jerry Mael