Last post on Apr 29, 2013 at 10:31 AM
You are in the Chevrolet Silverado & GMC Sierra
What is this discussion about?
Chevrolet Silverado 1500, Chevrolet Silverado 2500, Chevrolet Silverado 3500, GMC Sierra 1500, GMC Sierra 2500, GMC Sierra 3500, Heating / Cooling, Truck
#360 of 369 Re: Sierra A/C compressor comes on in heat mode? [rickiev]
by kcram HOST
Feb 25, 2012 (6:39 pm)
The compressor will definitely come on if you're using the defroster, as the compressor and evaporator work to dry the air - otherwise, moist air will freeze on the inside of the windshield once it's turned off. Check your owner's manual to see if the defroster is automatically activated below certain external temperatures upon first-start./warmup.
kcram - Pickups/Wagons/Vans+Minivans Host
#361 of 369 Problem with daul climate control/ No Heat...
Mar 07, 2012 (3:17 pm)
I have a 2005 Silverado 4X4 Crew cab. During warm up first thing in the morning with the truck is at or about 210 degress the climate blows cold until I start driving and then blows hot air. Also at temperature stopped at traffic lights/stop signs and at iddle the climate control blows cold air, while driving I have heat.
Further info... recent tune up less than 3500 miles, out of warranty, current mileage 87,050, 2nd owner of truck I bought it 2007 at a dealer.
Any help would be great. I would kind of like a idea before I spend too much for mechanic's diagnosis of the complete front end. No offense to any wrenches...
#362 of 369 Re: Problem with daul climate control/ No Heat... [swalker88hd]
Mar 08, 2012 (6:36 am)
I understand that you are looking to gather any options before paying for a diagnosis. We can check to see if there are any open recalls or anything on your vehicle for you if you wanted to send us the last 8 digits of your vehicle's VIN.
GM Customer Service
May 01, 2012 (1:22 pm)
I too am having unresolved intermittent dual climate control trouble with my 2004 Silverado. Last time in the dealership they said there was a TSB released for this problem. I've been looking for it on the web but I cannot find it. If someone has it I would appreciate a copy. Thanks.
#364 of 369 Re: Heater TSB [reteils]
Jun 18, 2012 (3:36 pm)
This reply is for reteils on post #363. the info you are asking for is NHTSA #10012173/ TSB #040138008. I have replaced my instrument cluster and heater control module at my own expense due to mileage and poor timing on recalls by GM. However, I am still having the most common problem as everyone else here on the A/C unit blowing hot air on the driver side, etc.... Sounds like this has been an issue for over 10yrs now. I'm a full blown Chevyholic, but I am not impressed with these issues not being addressed in a decent amount of time. If anyone can pinpoint me an answer w/o taking my 2004 Silverado to a shop I would greatly appreciate it. All repairs have been not so cheap, but have easy so far.
#365 of 369 Re: Problem with daul climate control/ No Heat... [swalker88hd]
Sep 30, 2012 (3:24 am)
Sounds like you might be low on coolant, which would not allow enough pressure to build up to open you thermostat to get your heater core warm enough at idle. Also you may have an air pocket caught in the system. Google how to bleed the system if your mechanically inclined enough(not saying your not) but i have ran into similar problems on my older Chevy. Plus both are pretty much cost free to check yourself which makes it even better
#366 of 369 Re: 2000 Sierra 2500 Heater Core "Connector?" [tmurphy1988]
Dec 18, 2012 (6:02 am)
My 2000 GMC did this I could not find replacements so I simply cut away the plastic and hooked the hoses directly to the heater core. It has worked fine for several years now
#367 of 369 01 Silverado AC only works after shutdown and restart of engine
Mar 27, 2013 (7:08 pm)
#368 of 369 01 Silverado AC only works after shutdown and restart of engine
Mar 27, 2013 (7:08 pm)
I can not turn the AC on until I shut off the engine and restart.
#369 of 369 AC/Heat Control Problems
Apr 29, 2013 (10:31 am)
My 2008 Silverado sometimes when AC is on, the unit swaps to defrost with heat by itself and vice cersa when the heat is on. Anyone know of a fix for this, Thanks