98 Blazer blower motor problems

Yet one more problem. I shut my blazer off and blower motor continues to run, until battery runs down. Could this be the resister? Where is resister located? Is this something I can change myself? When it doesn't turn off it only has one speed. When it does turn off it has all speeds and works fine. Of corse when I take it somewhere to have it checked out it works fine. Right now I have a switch hooked up to blower motor for a (just in case) it won't shut off with truck.

That circuit isn't supposed to have power when the ignition is off. First thing I'd do is see if the previous owner did some minority-engineering with the wiring.

Can you turn on anything else with the ignition off? Radio? Rear glass defroster?

That circuit isn't supposed to have power when the ignition is off. First thing I'd do is see if the previous owner did some minority-engineering with the wiring.

Can you turn on anything else with the ignition off? Radio? Rear glass defroster?

No, I can't turn on the blower either, it just doesn't shut off sometimes, which is why I have the switch hooked up to blower motor. Old owner was a company vehicle, kept it in excellent condition, bought with low miles 6 years ago, no after market modifications, 12 years old now and still looks and runs like new...would like to fix these minor glitches. It's been good to me.

Only thing getting power AFTER the key comes out is the delayed accessory bus. That kills interior lights after you've locked up, it keeps the radio on until the door handle opens, and some other things.

I don't know how it could keep the blower powered up, unless there's a short from a mouse grubbin' on the wiring insulation (seen that). 'Sides that, ghosts? Stale air freshener? New moon?