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Ac Blows Hot Air(heat) On Passenger Side.

Z71kris

By Z71kris
in Ask A GM Technician

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Z71kris Senior Enthusiast

Z71kris

Posted
Posted

Hello, on my Z71 the AC on auto or manual setting blow heat to the passenger side, the defrost blows cold up to the window and down to the feet, also I noticed the fan sounds funny as well, as in its to loud, any help?

bill190 Enthusiast

bill190

Posted
Posted

There are typically little "doors" which open/close to do different things for an A/C - heating system. These doors are many times electrically operated. And an electronic control module controls their movement.

 

One door may bring in fresh air in one position and recirculate the air in another position.

 

Another door may direct the air to the floor, vents, or defrost.

 

Another door may turn on/off the heating by allowing (or not allowing) air to flow through the hot heater core.

 

Because these are electrically operated usually, I would check your fuses.

 

And electronic things are not happy when there is not enough voltage, so measure the power on the vehicle with a multimeter to be sure it is not a low battery.

 

Sometimes electronic things can get into a "confused state", so might try disconnecting the battery for about 5 minutes. Then reconnect. This would be like "rebooting" a computer.

 

Then to troubleshoot this problem (if no one else can tell you the specific problem and what to do), you would need a multimeter and a factory service manual set. This would include a service manual book which would describe how your climate control system operates and would give detailed troubleshooting instructions and instructions on replacing the various components. And also would include an electrical diagram manual which you could use to test various components, see which fuse(s) power comes from, the location of electronic modules in the vehicle, etc.

VMax2007 Senior Enthusiast

VMax2007

Posted
Posted

Yeah, you can do all that ^^^ and then afterward head to your dealer for a Blend Door Actuator. That is what you'll need. :dunno:

Z71kris Senior Enthusiast

Z71kris

Posted
  • Author
Posted

I shall try disconnecting the battery, and hope for the best, I don't want to sink much in her, she only gets drove when I need to tow/haul, considering me and wifie car-pool now-a-days, and we take her TB most days..

superjim Senior Enthusiast

superjim

Posted
Posted

sometimes you can cycle the heat/ac controls SLOWLY from full heat to full cold a couple of times and the doors will readjust themselves.

Z71kris Senior Enthusiast

Z71kris

Posted
  • Author
Posted

I dont know what happened but after I finished my air filter cleaning I was going to disconnect the battery for a bit, but I figured I would try the AC just to see, and it worked perfectly, so I dont know what happened but it is working again for now

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