OK let me start by saying my Tahoe(96) has gremlins. I had at one time installed an aftermarket HU and used the proper wire harness and everything was working fine. I used my truck one day to hotshot (jumpstart) another vehicle. After several minutes charging the the other trucks battery I still couldn't start the other truck. I then unhooked everything and suddenly my stereo would not work. I would turn it on and the display would just flash. After a couple of posts on this forum I was armed with some possibilities for fixing the problem. After awhile I gave up and put the old stock Delco stereo back in the truck. I could turn the stock stereo on and it seemed to work OK until I turned up the volume loud and then it would go crazy. The back speakers would stop working and I couldn't control the volume of the front speakers. For the last 6 months or so the clock wouldn't keep the time when I shut the truck off. My presets were still there but it was 1:00 o'clock everytime I got in my truck. I finally replaced the battery in my truck two weeks ago and the radio would now keep the time. No more groundhog day. I still had the problem with the speakers shutting off when I cranked the volume so I decided to try a different head unit. I had a couple laying around so I installed an Aiwa because it has a aux /in on the front for my MP3 player. Anyway I hook it up with just the front speakers because I planned on bypassing the factory amp that powers the rear door speakers and running wires from the HU directly to the rear door speakers. With just the front speakers hooked up everything was working fine. I hooked the back speakers up to the purple and green wires from the HU and I get no sound from the front or back. I unhook the back speakers and the front works again. Does anyone know what is going on here? BTW I also tried it with a Sony HU and a Pioneer with the same results.
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my dad has a shovel
try finding some speakers laying around that you know are good and hooking them up right behind the radio on purple or green (bypassing all the stock wiring). if it works then there is a short in the wire(s).
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Thanks SS. The wires I had running to the back speakers are brand new wires. I ran them right from the HU directly to the speakers bypassing all the factory wiring. I did this because of the problems I had before. Could the problem be that the speakers combined are causing the amp to drive a load that it is not rated for?
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my dad has a shovel
how many speakers do you have hooked up? most head units will handle 2 ohm stereo. are you sure the speakers are good? if the clips come off the speaker and ground out then it will shut the deck off.
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Right now the stereo is working fine with just the front factory speakers. It appears to have a full range driver and seperate tweeter mounted in the door. Once I connect the back speakers the front speakers stop working. I disconnect the back speakers and the front works again.
The rear door speakers were oringinally hooked up to a small factory amp. I cut the speaker wires about 3" away from the clip so I could bypass the factory wiring. I soldered to the wires that came out of the clip to the wires I ran to the head unit. The clips remained connected to the speakers and are tight.
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my dad has a shovel
The rear speakers have to be shorted in one way or another. The short is causing the internal amp of the head unit to shut off to protect itself. Try removing the rear speakers so they are not touching the door at all and see if it works.
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Good Luck!
-Thad
I agree it sounds like a short, you did tape around the solder splice right?? You might want to check the impedence on the factory speakers also. Especially if they where amped seperatly. I know a while ago Bose used to put in car speakers that were all kinda of wierd impedences so who knows.
Also, I once (very carelessly) was jumping sumones car and hooked up the poarities wrong 
well that fried his stereo instantly and messed things up quite a bit. I dunno if that has anything to do with whatever ...but there you go. Good luck!
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'97 Jeep Cherokee sport
subs: JL 12w3v2 : RF 500a2 :
RF 1F capacitor
doors: 6" Diamond D361i -> RF 200a4
Thanks SoundAudio.
I will give it a try later. It's so hot here that I might have to wait a few days for it to cool down. I don't know if I can stand working outside in the heat.
Anyway if this doesn't work I have an amp that I can wire in. I know the rca's work so I may go that route if I can't find the short.
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my dad has a shovel
I installed a power amp and I am running the rear door speakers from the amp and everything seems to be working fine.
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my dad has a shovel