2006 gmc sierra 1500 sle AC blower working intermittently

[mbecke2]

GMC sierra 1500 with 70,000 miles. Digital climate control ac unit. Very recently I turned on my AC and the blower did not come on at all. Then all of a sudden it worked perfect, so I thought it was a fluke. Then it got worse. Now it is intermittent. Comes on but only blows at level 1 even if I crank it to level 6. Then sometimes works fine. Sometimes does not blow at all. Air is cold, just a matter of getting the blower to blow it out to me. What happens now is I turned it all the way up to max (level 6) and it barely blows like its on level1 and then I start praying. Sometimes it kicks in and blows great, sometimes not. Also I hear some clicking near the motor whenever it gets ready to kick in and start working. I took off the blower resistor and inspected it. The resistor only has 3 wires coming in (red, black, purple) as most I've looked up have 5 or 6. The female harness for the red wire looked a little burnt but not bad. My question is how do I make sure it is the resistor before I just throw parts, or can it be something else. What controls the different speeds (Im assuming the electronic board behind the dash- seems hard and expensive). Im hoping its just the resistor, just wanted to check with the experts. Thanks for any input.

[bossier62guy]

Are you sure you've got a resistor in your system? The red wire comes from a 40a fuse under the hood labeled BLWR. The purple/white wire comes from your HVAC control module and is labeled blower motor control speed. Of course the black wire is ground. They all run to the blower motor control processor. I don't think you have a "resistor" like the manual HVAC systems. Whether the control processor or module is causing your problem....not sure. And you should have 5 wires....3 incoming, 2 going to the blower motor itself (purple/black). If the wiring is good without a scan tool it's a crap shoot.