I have a 2001 Bonneville SLE without bose if that matters. Recently the Front passenger side and the rear drivers side speakers stopped working (no noise at all). Today i replaced the rear speakers and im still not getting anything out of the drivers side rear. Now before i buy speakers for the front is there a possiblity that the front is not blown either and that there is another problem that would cause those two speakers to not work?

the fade hasn't been changed has it? that would be the first thing to check

Nope the fade and balance are fine.. tried them in the middle and tried changing to just those speakers

thats strange, 2 seperate channels would go out on the same side, I've never seen this on any of the cars i've worked on, maybe someone else will have some helpful info

the outputs on the radio may be fried. id check with a multimeter to see if there is any voltage behind the radio being put out to speaker (+,-) wires for all four speakers. if you want to check the speakers to make sure they arent blown, touch a battery to the speaker terminals with a few loose scrap wires + to + and - to -. the speaker should pop and you should see some cone excursion. If they dont pop... dead speaker.

Can i test the back of the radio? It is the "dock and lock connecter" not just wires coming out the back? Is there a way to test this?

My mom has an 02 bonnie can i swap the radios to see if the head unit is bad or will this actiave the theftlock?

the theftlock will probably kick in, yeah it will be hard to test at the radio connection because of the flat wire, convienient for quick installation but a pain in the *** for testing and tapping wires

gooper, crunk is right, that radio does create a problem for probing or using wires behind it as signal sources. I guess the best way that I can explain to you what needs to happen would be done by saying (and please dont take offense to anything i say that sounds too elementry. I just want to make sure that I give you and anyone else reading the best input i can without being there, and a way for you to visualize how you can track down the problem), in an electrical problem there are 4 areas that you can almost always find the sollution
1. the power to the source signal- this is really a simple way of saying you want to make sure that your source signal(the radio in your case) has power and ground and works. since your radio does come on lets move to step two.
2. the source signal- (in this case your radio) now you normally would be able to test what the radio is putting out if it were an aftermarket (or different radio) by putting it on a test bench, feeding it 12v constant and switched and ground. when you turn up the volume (with a cd playing) you could check each pair of speaker wire to see if its putting out any voltage. It should read something low i believe like 4-7 volts but i could be wrong. if all of your speaker outputs are showing voltage you would then move to step 3.
3. the pathway- this would be whatever wire is between your sources signal and the source itself. in your case it would be speaker wires. this would be done by checking the speaker wires between the radio and speaker in different locations. I will be honest, this step is most often step 4 because it could be a pain in the ***! not to mention the fact that as a trouble shooter, we often go to whats wrong first and work backwards. either way is fine but if you check your speaker first and its doin nothing, the easiest next step would be to pull the radio instead of following wires behind a dash, to the kick panel and then through the dreaded molex plug. i guess you already know step 4...
4. check the source (whatever it is all running to)in your case your speakers. pop them with a small 9volt batter by running some scrap wire from the (+) of your battery to its matching terminal on the speaker and the same for the (-). if it moves and makes a popping noise chances are it is fine. You could also check the impedence of the voice coil by setting a volt meter to ohms and touching the black lead to (-) and the red to (+). If it doesnt read anything the speaker is blown.

Again, this sequence is used to try to isolate an electrical problem and will most likely expose the problem. I will also stress that the most common way to troubleshoot a car audio system is by doing whats easiest first but if that gives you no progress follow these steps in order. I can help you along the way if you have anymore questions. That is what us Gear Heads are here for (well that, and hazing eachother but thats just what everybody did to me when i first came on the forums... hahaha thanks guys. Anyway, let me know if you need me

Ok... It turned out to be the head unit. Picked one up at a local junkyard for 50 bucks, Had it programed to my car at a local dealership (Its great to have friends, got it done for just a tip to the tech, said they usualy charge 84.95) Thanks for all your guys help