My front speakers and sometimes my left rear speaker don't work. I know it is not the radio cause I tested it on some other speakers and it works fine and I know that all of the speakers are not broken because I checked them and they work also. I'm guessing it's the power amplifier but I don't know where they put it. I asked one of the guys at the jeep dealership and he said they are under the passenger seat but they arn't.

 

It is under the rear passenger seat in both my Grand Cherokees

 

under the rear seat on my '97.

 

under the back seat on '99

 

Mine too. It sucks though.

 

did you check and make sure their isnt a break in the wiring? or in mine the wires were getting squished when i put my pioneer deck in cause it was a little too big and that caused the wires to get pulled out a little