2004 ENVOY WHERE IS MODULE RESISTOR

Most likely the resistor has shorted to hot. It is close to the blower.

I'm showing a blower relay and a resistor used on models with manual ac control.
The blower motor is grounded and the fan switch provides power thru the resistor. So you have a 40amp blower fuse that handles high thru the relay, then a 30amp HVAC fuse that powers the blower thru the fan switch.
Do you not have power from the resistor to the blower motor on the purple wire ?

The relay in your blower motor is stuck on, there is a TSB for this issue. Replace the blower motor resistor and you'll be back in business.
How does the resistor get power if the fuse is pulled?
Replacing the resistor will cure both problems. TSB is a technical service bullitin seen below
Subject:HVAC Blower Motor May Run Continuously After Vehicle is Turned Off (Replace Blower Resistor Relay)Models:2004 Chevrolet Avalanche, Silverado, Suburban, Tahoe, TrailBlazer, TrailBlazer EXT2004 GMC Envoy, Envoy XL, Sierra, Yukon, Yukon XLwith Manual Control HVAC (RPO CJ3)Built Prior to August, 2003

Doesn't have a resistor. It has a blower motor control processor. When they go bad, the blower motor defaults to always on (go figure that logic). Pull the AUX blower motor fuse until you can get a replacement. The processor is located back by the rear blower motor.
Blower motor wont shut off Ricks Free Auto Repair Advice

{: ) Check out the J-case fuse (square) labeled BLWR 40amps at the underhood fuseblock. This fuse is the source of power to the blower motor when position 5(max speed) is selected. If this fuse is tested to be okay, you need to access for the blower resistor connectors. Turn ignition on, and set blower to max speed (#5). Probe on the blower resistor terminal (orange wire) and you should get 12volts, also probe the terminal (red wire) which came from the 40amp fuse. 12v should be present on these two terminals at the blower resistor when at max blower speed. Particularly on the orange wire, if you don't get 12volts when at #5 position, it 's probable that the blower speed control switch is faulty. But if you did got 12volts during the procedure, then you should replace the blower motor resistor. Goodluck.

{: ) Check the underhood fuse labelled BLWR (40amp). Check the rear fuseblock fuses labelled HVAC (20amp), HVAC1 (10amp), and HVACB (10amp).
The next most common cause is a faulty blower resistor.
You may also have a malfunctioning blower; it could be stuck, or open circuited, or the connectors are faulty. The HVAC controller is also a possible culprit, although it seldom happens.

Sounds like the blower motor resistor module is bad. It is located behind the glovebox and mounted to the blower motor. Open the glovebox and in the back left corner find a spring, push on spring to release glovebox door completely. You should be able to see blower motor and resistor module.

Replace the fuse back in the fuse box,and replace the blower relay(module)to repair the problem,it is near the blower motor.

replace the blower motor speed control module, it is shorted.

youve got a short prob right at the switch in the dash,unplug the switch and if it shuts off then replace it,if not run new wires form the fan motor too the battery thru a toggle stwich