Fan Control

jtstacy77 · May 13, 2011

With the temps getting hotter and pollen in the air I have started using the AC. The problem is the fan works on 1,2,3, and 4 but stops when i put it on 5. Could it be that the contacts aren't touching on 5, but they are on the rest of the settings? If so can it be repaired or should I just replace it? Thanks in advance for any advice!

plowking · May 13, 2011

I'll give it a shot. On the older chevys I have dealt with,it can be bad contacts behind the switch or the resistors, they are located in an opening on the blower housing. I took out my switch in the dash and unplugged it and replugged it back to harness,mine came back to all speeds. I also bought the resistor,it is a little black box,inside each speed is fed thru it's own squiggly wire,it reduces a certain amount of voltage or wattage depending on speed settings The resistor box has a plug in for the harness. plowking

MikeNH · May 13, 2011

If 5 isn't working then it may be the high speed fan relay. The resistor pack only controls 1-4 I'm pretty sure and 5 has it's own dedicated relay. I would look at this before the switch, the switch is low current only and failure there is extremely unlikely.

jtstacy77 · May 13, 2011

If 5 isn't working then it may be the high speed fan relay. The resistor pack only controls 1-4 I'm pretty sure and 5 has it's own dedicated relay. I would look at this before the switch, the switch is low current only and failure there is extremely unlikely.

Where is the high speed fan relay located? Thanks again!

MikeNH · May 13, 2011

If 5 isn't working then it may be the high speed fan relay. The resistor pack only controls 1-4 I'm pretty sure and 5 has it's own dedicated relay. I would look at this before the switch, the switch is low current only and failure there is extremely unlikely.

Where is the high speed fan relay located? Thanks again!

I traded my 03 in 3 years ago, I don't remember anymore. Hopefully someone else can chime in, sorry!

jtstacy77 · May 14, 2011

I read a few forums on the trailvoy forum and found out that those vehicles have a seperate fuse under the hood for the high speed. Could it be the same on the avalanche?

NOS · May 14, 2011

Its the blower motor resister.Most likely it melted the harness connector too,very common.

I replaced mine last year and just got recall notice from GM Canada a few weeks ago so they know about the problem.

Not sure if there recalling in the states though.

8.1HD/ALLISON · May 14, 2011

Its the blower motor resister.Most likely it melted the harness connector too,very common.
I replaced mine last year and just got recall notice from GM Canada a few weeks ago so they know about the problem.

Not sure if there recalling in the states though.

+1 They had problems with the blower resistor connection. Passenger side of dash there is a flat connector with about 5 or 6 wires near the blower motor. That is the resistor. Remove the connector and see if any terminals look burnt.

jtstacy77 · May 15, 2011

After searching blower motor resistor on the forum search, I found that there is a possible recall for 02-07 full size vehicles. Though alot of people contacted the dealer and found out there vehicles vin isn't covered by the recall. Any suggestions on how to find this recall?

fraiolib · May 15, 2011

After searching blower motor resistor on the forum search, I found that there is a possible recall for 02-07 full size vehicles. Though alot of people contacted the dealer and found out there vehicles vin isn't covered by the recall. Any suggestions on how to find this recall?

call your local dealer and give them your vin and see if its covered.........