OK I know its a tractor site but hell I drive a truck too. OK the problem is this, the truck has duel temp controls, now sometimes when I start the truck one side will stay cold as the levers are in the cold, and the other side will blow hot air, which in the winter wouldn't be to bad but not now. Now if I turn the truck off and restart, most times it will go to cool, sometimes not. The temp controls are not being moved at all both on the cold setting, even with the AC the one side will blow cold air and the other hot. So Im looking for some place to start on the old girl, oh 04 Silverado 5.3 4wd I don't know if that means anything but they always ask me at the parts store
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Daren Todd
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Neighbors got an 04, and had the same issue with his. Passanger side quit working all together. If I remember right on his, it was something in the puter and they had to replace the whole unit.
85Hokie
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I have seen similar things with other makes, on occasion unplugging control unit and plugging back in will clean up a dirty connector. Kinda step one for diagnosis. Hvac now uses a memory circuit, live battery so a bad power/ground will make them whacky.
Just did a quick search, you arent alone.
Losing its memory during startup tells me weak battery or dirty battery connections.
Generally after a battery change heater needs a recalibration.
Just did a quick search, you arent alone.
Losing its memory during startup tells me weak battery or dirty battery connections.
Generally after a battery change heater needs a recalibration.
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Grouse Feathers
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Lil Foot
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I know several people with Dodge trucks with the same symptoms- turns out there is a diverter door in there somewhere with under-strength plastic hinges that break regularly. One guy I know must have had a dozen replaced under warranty. Maybe the heat out here is hard on them?
This made me laugh, because nowadays people in the parts store are clueless without the computer.
We joke that you could go in for a screwdriver, and they would not be able to help you until you tell them the year/make/model/engine size.
Grouse Feathers
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I had the same plastic damper break in a 07 Ford with automatic temperature control. I think the automatic control moves the damper a lot to maintain the temperature and the damper eventually fatigues. Big job on the Ford to remove the whole dashboard to get to the heater system for replacement.
My 2013 does not have the automatic control.
Chevy has a blend door motor w/plastic gears. If you hear a clicking sound when you start your truck that's what is bad. I've read they're fairly easy to get at and change although I've never done it.
RCW
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Skeets - you had me swingin' on that one, but sounds like it happens for various reasons as the other guys said. (My '13 is my first with dual controls)
How did you make out on the Check Engine light a while back?
How did you make out on the Check Engine light a while back?
I had to replace the sensor in the exhaust pipe before the cat, we got that out and the freekin thing was cross threaded from the factory,, had to find a tap not a good thing to be looking for on a Sunday . The nephew cleared everything and the light went out,,, then back on after about a week when for some reason it started missing really bad,, Then it went out and yesterday it came back on, and now its out,, so I have no freekin clue,, Im just about ready to park it, where the brothers gather, with the key in the ignition and walk away windows down and doors unlocked. That wont happen but Im starting to feel that way
That 02 sensor was likely not cross threaded, but galled threads. Have come across it a few times. I use a spark plug thread chaser to repair damaged threads.
As far as sensors go i usually change them both at once.
We are getting off original topic.moderators are gonna spank us...
As far as sensors go i usually change them both at once.
We are getting off original topic.moderators are gonna spank us...
LOL yeah I guess we need to get back to the hot air thing,, It did something strange today,, was blowing cool air,, and then after about 20 min poof hot air again,,, I really don't want to rip the dash board out
Common problem on the gm to do that, according to a general repair shop that does work for me. Something in the dash that has to be replaced.