Hey guys, I drive an '01 Silverado Ext Cab 2WD D/A and I was running the AC on max air 5 yesterday and it kicked off then on and then off and stayed off. It runs on the 1-4 settings but nothing on the 5 spot. Any help would be GREATLY APPRECIATED!!!

Assuming it's just a blower issue, start with 30 amp fuse "FRT HVAC" in underhood driver's side fuseblock. I just accidentally lost my 20-line dissertation of wiring colors and connectors. Your gain probably. There is a 1-row A-G harness connector facing down from blower resistor ass'y mounted up into plenum from underneath, underneath right end of instr panel. The relay trigger and battery for blower-hi are the smaller and large orange wires, respectively, at one end of that connector. Maybe it's cocked and coming apart. Should be full-time battery from underhood fuse on big orange G, and battery from blower switch only in position 5 on small orange F, and relay within that unit should operate on switch pos 5. Let me know if you still have trouble.

Check the fan motor for continuity with a ohm meter. If open circuit, the fan motor needs replacing. If close circuit, try to run power directly to the fan motor to see if it blows on high. If it does, then check the fuseblock or fan switch.

"It runs on the 1-4 settings but nothing on the 5 spot"


Motor can't be too bad...

Thanks for all the advice guys, although I'm not a mechanic and don't really understand most of what ya'll are telling me, Im going to keep trying. If you have an easier way of explaining what you are trying to say great, if not, I understand and will keep trying. Thanks again for all your advice, its nice to know theres a place a man can come and ask questions without looking too stupid. Any thanks again!!

OK, I checked the 30amp fuse and its OK, I checked the F and G wires and the G has 12v always and F has 12v in the 5 spot, so I guess the blowers getting the power it needs it just isn't turning on. This is as far as I've gotten so any further help would be greatly appreciated!! Thanks in advance!! Jay

In position 5 if the large orange wire and the small orange wire have power then the purple wire to the motor should have power. If not, the resistor assembly is bad.

The purple wire does not have power in the 5 position. Were is the resistor assembly located and do you have a part number? Thanks in advance!! You guys are great!!

my fan didnt doesnt change between 1-3.... then 4 &5 blow ya away...took it in and resistor was bad...had to order it so dont knwo if it works yet....
on a stupid note- i didnt notice it for almost the first 4-4.5 months i owned it....i always thought it was tied in w/the climate contorl.....http://www.dieselplace.com/forum/smileys/Embarrased.gif

I got it fixed guys, it was the resistor ass'y. I appreciate all the help ya'll gave. Thanks again!!
Jay

Just for the record, 'cause I'm one of those precise, anal, mf's: It wasn't the actual resistors or the purple wire to motor, though, per the schematic. "1-4 works correctly" is proof of that. It had to be the relay or its connections within the "resistor ass'y"... Glad to hear you got it fixed, and good call GMCSID.