[skyzend]

I just replaced the blowerand resister pack in my 1999 Blazer.

I can't commentv on the switches burning up as miner were fine but ....

Just prior to replacing my blower I was losing speeds. Before the fan finally gave out I only had high speed none of the other speeds settings worked.
Now with a good fan I started checking and pulled the blower resister coil assembly from the firewall.

You have to cut into the rubber housing assembly to get access to the mounting screws. Just cut along the recessed "cut" outlines and you will be fine. It will likely be necessary to remove the flat copper ground connection from the firewall as this is any easy thing to do and makes access a whole lot easier.

I checked the resistor paths with a meter and found that the paths were all broken circuits ... ie the resistors were toast. The high speed has no resistor path so that one always worked. The replacement cost a little over $20. When checking the resistor values, most are very low ... less than 1-2 ohms. actually there is a wiring diagram on this site somewhere in the help threads that give the exact values.

Hope this helps, Once the rubber housing is cut, the resistor coil assembly can be replaced in about 5-10 mins. Reseal the rubber housing back over the access bolts when done using black window sealer/adhesive or similar product when you finished.