Well to anyone who has this problem then listen up. If your heater only works on certain levels like 3, 4, &5, then only works on 5 and finally goes out then your heater resistor went out. It is an easy fix as long as you have bendable ratchet extensions or a snake like device for a ratcheting device. I didnt have the tools to get to the bolts so took it to a shop. Now I got the glove box and other dash parts taken off and two of the bolts out of the blower motor before hand and also bought the part from autozone for $35. The shop got it done in 30 min and only charged me $35, so I spent $70 to fix the problem.
If you look online at repair topics on this you will get different answers to replacing this but I can tell you on the 01 body style you will need to do the following:
take of glovebox
remove plastice trim and fuse cover
pull off lower carpet trim and full back the carpet
take off the blower motor and spin it to make sure it is still good as well
take out the resistor which you only take out one bolt and loosen two others because the holes are slotted, then unclip the wiring
After that you just replace with the new one and work your way back
