Symptom of a faulty blower resistor is, blower only works on speed "4". I got my replacement resistor for $24.99 from Autozone part # JA1476 AutoZone.com | | Blower Motor Resistor | BLOWER MTR RESISTOR
below is just a guide on how to replace the blower resistor, although maybe not the best way, it's the way I did it.
first to remove glove box, slide out the retaining strap on the right side then lower door till you can pull it off the hinge
Next I removed the interior light just under the glove box (1/4"). This made it easier to remove the resistor. You can use this as a work light or just remove the bulb so you don't get burnt.
Then from above though the glove box opening, I used a 1/4" drive 8MM (5/16) swivel socket with extension and ratchet to remove the top screw (one of two screws holding the resistor), seen just under the brightly colored connector.
Then from below I removed the bottom screw using the same 8MM swivel socket set up.
With both screws removed I just slid the resistor out of its location then pulled the harness downward (why I removed the light) you can now see why it's faulty (burnt)
Now disconnect the resistor plug by first releasing the plug retaining clip, pull the red clip out slightly. (sorry for the blurry pic, camera got fogged up. it was very humid out) first pic shows the red retaining clip in the lock position, the second in the released position
in the below pic you can see the difference between the new (now plugged in) and the old burnt resistor (in my hand).
Here's a pic of the old resistor and the box the new one came in.
Well just reverse the above to install and enjoy your lower blower speeds again.
Note: do not use the blower with the resistor removed (not in it's proper place in the blower's air stream) or you can burn it out.
Disclaimer: some of the pictures were taken during reassembly because of the fogged up camera.