climate control screen went blank

2004 CHEVROLET TRAILBLAZER
70,000 MILES • 6 CYL • 4WD • AUTOMATIC
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FLAMINGO1ONE
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The climate control screen on my TB went blank and none of the controls (AC, Rear defog, fan speed, temp controls, etc.) work. Not sure if this is a computer issue as all of the other systems seem to function fine.
Nov 5, 2008 at 11:36 PM
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JAMES W.
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This may sound very basic but, the climate control system is on a seperate fuse. Is this fuse good?
Nov 6, 2008 at 12:55 PM
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FLAMINGO1ONE
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Jim,

Have looked at most of the fuses which aply to the HVAC system, can you tell me which fuse as I do not have a schematic.

Thanks,
Steve
Nov 6, 2008 at 1:17 PM
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FLAMINGO1ONE
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Just went through all fuses and all look good is there a point which I can check for power?
Thanks,
Steve
Nov 6, 2008 at 2:01 PM
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JAMES W.
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Steve, sorry it took so long to get back to you. My information source has been down and I just got it back yesterday. Anyway, What we need to do to test power to your climate unit is to pull it out of the dash so you can unplug the connector(s) from the rear. With key on, connector terminal E should be + voltage. Term D should be - or ground. If for some reason these term.s don't read right, look for any terminal that is hot with key on and dead with key off. If this part checks out, there is a problem inside the unit. I don't think you will find a fuse inside but there might be. Nowadays, you never know and I couldn't find a diagram to tell me. You can check in your area for an electronics repair facility or a dealer may have a rebuilt unit available. Wish I could tell you more. Jim One more thing, you may have 2 hot circuits at the connector. One for system power and one for the LED screen.
Nov 14, 2008 at 10:19 PM
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PLAYTUNE
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Hi,
I'm experiencing an issue with my climate control mechanism effecting my idle speed and causing engine to stall.
My engine runs fine until I turn on either the AC or Heat which is controlled by the climate control.

When I turn the climate control on the engine the engine will bogg down and when at a stop the engine will stall. When at driving speed I can feel the engine decrease power and then be normal and back to lack of power.

When I turn the climate control to off everything runs fine.
I replaced the MAP sensor because it was throwing a code thinking that might have something to do with it but it hasn't solved the issue.

Your help is greatly appreciated!

Thanks!

Brad Foll
May 9, 2020 at 1:26 PM (Merged)
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WRENCHTECH
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It's pretty much normal for the A/C compressor to add extra load to the engine. The problem is that the idle control is not compensating for it.

You may have a bad IAC ( idle air control) but try cleaning the throttle body first. Remove the intake snorkel, have someone hold the throttle wide open for you and scrub the back side of the throttle plate and surrounding bore with an old tooth brush and some carb cleaner. Be sure to spray some into the small holes next to the throttle plate. That should help stabilize the idle. If it still has a problem, replace the IAC.
May 9, 2020 at 1:26 PM (Merged)
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SQM
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Hello,

This Trailblazer is not equipped with an idle air control valve (IAC). The IAC function gets performed by the electronic throttle actuator.

Cleaning out the throttle actuator is a good first step. As dirty actuator can trigger idling issue and won't be able to adjust according to the engine load (when the A/C gets turned on, etc.).

Here is a helpful guide on cleaning the throttle actuator:

https://www.2carpros.com/articles/throttle-actuator-service

I have attached diagrams for your reference.

Please let me know if you have any questions.
Thank you.
Dec 8, 2021 at 10:32 PM