06 Tacoma aftermarket radio reciever

I bought my truck with an aftermarket pioneer radio. Only one speaker works some of the time. I pulled it out but it is a mangled mess behind it. I doubt all the other speakers are blown. I don't think the guy I bought it from knew what he was doing. Has anyone had eletrical issues with the radio and speakers in there trucks? I imagine it's probably aneasy fix I just really don't want to have to take the door panels off if I dont have to. I'm hoping I just need to rewire everything to the reciever.

 

There we 2 different radios.
One with an external amp, and one with an internal. (Not really considered an amp)
What system do you have?

Is it JBL?

 

It's an aftermarket pioneer.

 

I would bet the speakers are still good and wired properly at the speakers. I would pull the radio out and start sorting through the wires and find the speaker wires that are not properly connected in that mangled mess you describe. Make sure you have a good ground too.