HVAC Fan is eratic

[beav626]

it works and blows cold air but fan speed does not match what I choose on the Auto climate control unit.

If I put it to max fan speed I get very low air flow. If I put it in auto mode it shows full speed ion fan but the fan is putting out low speed.

Sometimes when I turn off the truck the fan keeps blowing.

is my blower motor going out, or my HVAC controls?

recently my blower motor was squeaking at me, so I took it out and lubed it. it is quiet but acting crazy.

 

[beav626]

Bump for Today

 

[beav626]

anybody?

 

[rv8tor]

I got exactly the same thing going on with my '05 Tahoe. Have you had any response anywhere else to this problem????

Jeff

 

[beav626]

I got exactly the same thing going on with my '05 Tahoe. Have you had any response anywhere else to this problem????

Jeff

yes- I replaced the resistor module next to the blower motor and everything worked great.

as long as you blower motor is working OK just not responding to controls I would replace the resistor module

its like $80 from partstaxi.com

HVAC Resistor module.

 

[rv8tor]

The resister module eh..? okay. Is it easy to get to?

Jeff

 

[Chucktown Mako]

Very easy. Under passenger side dash, on my '01 anyway. Remove long black cover, 3 screws, then you'll see it.
If it's different for your year, hope someone else chimes in.

 

[beav626]

my 03 EXT had 2 screws to remove the Sound insulator (Black plastic cover)

Then two screws held the resistor in place. I removed the blower motor to unplug the resistor. Blower motor just rotate out.

 

[rv8tor]

Thanks guys. I will give it a try and let you know how it goes..

Jeff

 

[rv8tor]

Okay, I replaced the module next to the fan, and now the fans blows. The only problem is that it blows on high 100% of the time, and the dash controls do not have any effect! What's even stranger is that even when I shut the engine down and take the keys out, the fan continues to blow. I have to unplug the power source from the car to the module to get it to stop so I don't run the battery down!

So what gives here? What am I missing?

Jeff

 

[beav626]

Did you get a new module or used? It sounds like a bad resistor
module still. Uess they sold you the wrong one. Maybe they sold you one for a auto hvac car but you have manual hvac controls.

It is possible to have the co trios go out too but my money is on the resistor module

 

[rv8tor]

This new resister module was a "new" part right from the Chevy dealer. I suppose it could be a bad part, and I will certainly check that out. That seems unlikely though to me. We will see...

 

[177mph]

SOunds ike your control panel is going bad.

 

[k2yota]

I have an 03 Tahoe Z71 and am having similar problems. I got in the truck this morning and my front ac was not working but my rear was and it was blowing cold . . after about 10 minutes of driving the front ac started to blow and it was cold. It did this a couple more times . . any suggestions. I live on Guam and am hesitant to take it to the chevy dealership because repair prices here are outrageous so I would prefer to fix it myself . . standing by for intput.

Thanks

 

[beav626]

I have an 03 Tahoe Z71 and am having similar problems. I got in the truck this morning and my front ac was not working but my rear was and it was blowing cold . . after about 10 minutes of driving the front ac started to blow and it was cold. It did this a couple more times . . any suggestions. I live on Guam and am hesitant to take it to the chevy dealership because repair prices here are outrageous so I would prefer to fix it myself . . standing by for intput.

Thanks

As mentioned above I would reccomend replacing the resistor module first. if that doesnt work it mauy be a control issue.

This new resister module was a "new" part right from the Chevy dealer. I suppose it could be a bad part, and I will certainly check that out. That seems unlikely though to me. We will see...

if the part is not bad and you need a new controller, I have a Autio HVAC controller out of my 03 Escalade that I am selling. PM me if you are intrested. waaaaaay cheaper than dealer prices.

 

[rv8tor]

Okay all... under the dash with the big long cover removed, there are two modules...one is the blower motor module and then another module of some sort. What is this one??

Jeff

 

[beav626]

The blower motor is the big round piece. The resistor module is the smaller rectangle piece right next to the blower motor. There are wires connecting the two modules.

 

[k2yota]

I found out that on my model Tahoe (electronic display for ac/heat) that it is not the resistor that I needed but the blower control module . . I ordered it the other day from rock auto and am hoping it gets here soon and am hoping more that it corrects the problem.