2001 Blazer with auto climate. The blower would stay on even with the truck off and key out.

Got a new AC Delco HVAC blower motor control module. Connect up the harnesses, there's one connector/one wire that is supposed to get grounded against he blower motor housing screw.

When I connect it up, I get some sparks and it pops/blows the hvac 30amp fuse thats in the fuse block under the hood on the driver side.

With the module that was failed, I knew the blower motor worked. If you connected the single wire to ground, the blower motor would fire right up.

Fuse for HVAC in the driver door jamb is fine.

 

I'm about to drive this thing off a cliff I hate electrical that much.

All the wiring from the module to the fuse block looks good, not grounding out.

As soon as I set the ground wire of the 3 wires to the blower motor screw it pops the fuse.

 

Hook up the old hvac control module, when you secure the ground the blower fires up with the truck completely off with no key. However the fuse doesn't blow.

However, if leaving it going, get in the car and turn the key to the run position - I can't control the air. blows out the dash and that's it.

If the control unit is toast, that wouldn't cause the fuse the blow I wouldn't think...

 

If I pull the HVAC1 fuse in the driver door jamb, the blower motor still comes on with the older hvac blower motor control module.

 

So through all this, it was my blower motor blowing the fuse when the new module was installed. Strange I know - but I got a new blower motor in and now it works - no fuses blowing.

My problem now is, after recalibrating the HVAC controls, it seems like the force of air coming out of the vents is far from full power. I can change directional, and temp....but it's seriously lacking power.