The heater / Ac blower only blows on 1,2,3, speeds and not on high
where is the high speed blower motor resistor located

Try looking behind the windshield washer fluid and coolant overflow tanks under the hood. Can't be certain about a '00, but that's were my '96 is at.

I've posted before on this. My'97, the sealant GM used ate a printed wire on the resistor block that turns on the high speed relay, which is on the resistor, on the heater box, behind the reserviors.
I soldered in a wire to replace the printed wire.

The heater / Ac blower only blows on 1,2,3, speeds and not on high
where is the high speed blower motor resistor located

Same location as other post..but! could be a simple seperate fuse for the high speed circuit. Fuse is in the underhood fuse box. High speed circuit is actually a relay around the resistors, but located in the same pack.
I had an interrmitent problem with the high speed. Changed the fuse even though it looked good..may be small crack that I cant see. Will know soon..good luck.

I just fixed one of these with the same problem. Found a burnt connection where the red wire runs into the blower relay. You have to take out the overflow and washer tanks and then you will see a bunch of wires going into one plug. Pull the plug and you will see that the connection for the big red wire is burnt. I cleaned it up and put it back together and all speeds work again.

Was not the fuse. Finally had to replace the resistor pack. Got an aftermarket for about 23 bucks. You need to either make the opening a little bigger or cut off the plastic guides on the new part or it won't fit. good luck.