Rear AC Not Blowing At All

[fornesto]

First post - I did search here and everywhere without luck. So, my rear AC does not blow at all on my 99 Tahoe LS. I've replaced the fuse with no luck. I turn the switches and nothing happens. The front works fine. Any thoughts are appreciated.

 

[TxDrewski]

What you can do is get a short finder so you dont have to keep replacing 30A fuses, but unplug the relay in the back for the blower motor & see if the short is before the rear HVac or inside the rear HVAC.

If it doesnt blow then insert the relay & unplug the blower itself & see if it is the problem. Maybe it or a short in the wiring somewhere

Video that may/may not help
http://www.youtube.com/watch?v=Z2h3ewDYB2o

 

[fornesto]

Thanks for the quick response. I should have been clearer. The fuses are fine. They are not blowing, so I don't think I have a short issue. Sorry for the confusion.

Thanks for the link. I have a '99, but its the old body style. Can I assume that these rear a/c systems are pretty much the same?

 

[TxDrewski]

Ahhh okay, I thought they were blowing and thats why you replaced the fuse lol...
Id say a bad blower motor, or bad motor resistor.

---------- Post added at 06:47 PM ---------- Previous post was at 06:43 PM ----------

Here is a link to another forum where someone had the same issue.

http://www.tahoeforum.com/archive/index.php/t-8705.html

 

[SunlitComet]

probe the yellow wire going to the blower and to a ground for the power circuit test at any speed for juice if you have power for the most part you likely have a broken motor. if you have no power at all including at the high setting there is still a big fuse in the under hood block and should be rated at 50 amps. It is labelled "blower" in case you overlooked those fuses. Using the high setting bypasses any resistor so you can use that in the process of elimination.

 

[fornesto]

Thank's. I'll do that. Is there, by chance, a relay behind the driver's side dash? When I turn the front switch for the rear A/C, I here a quiet clicking.

 

[SunlitComet]

For the rear blower those relays are in the rear housing. You may be hearing the compressor cycling or another unrelated module at work.

 

[fornesto]

OK. Nearly three years later, I finally got around to this. I opened up the rear panel and took out the motor only to find the basket completely covered in thick black hair. I'm guessing the PO kept a Newfoundland dog back there and it sucked all of the hair in. I removed the hair, tested the motor (it worked) and put it all back together. Needless to say, it all works fine. Lessons learned - 1) sometimes the solution is very simple and 2) don't keep a big hairy dog right next to the intake. Thanks for the advice.

 

[MT Tahoe]

I think my German Shepard's hair may have clogged my blower. Do you have any advice for accessing the blower motor? I've removed the screws of the trim at the second row of seats and the trim at the base of the rear doors as well as the piece that has the door lock button. I am having an issue removing the piece under the window that covers the rear AC. Thanks in advance.