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2001 Silverado AC stuck on heat


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Posted

2001 Silverado 5.3. Compressor comes on and stays on. The line going from the compressor to the drier is ice cold and so is the high side line. AC worked fine last summer, heat worked great all winter and now it won't blow cold air. Any suggestions ? I don't have any gauges but can get some if need be.

Posted

The blend door is probably stuck.

 

Either the actuator is bad or the door is physically stuck.

 

By verifying the compressor is operating and the lines are cold rules out the A/C pressure system is at fault.

 

The blend door actuator going bad is pretty common and not that bad of a job to repair.

 

Is the vent/floor/dash blowing as set/expected?

Posted

Yes you can change it to defrost,foot,etc... Is there a way to manually move the blend door ? Also a friend suggested the ac controls could be bad (as in the switch that changes it from hot to cold ). If so is there a way to test that ?

Posted

I have never found a failed control unit other than flat out failed. As in none of the functions other than fan speed worked.

 

Testing is pretty much getting to the blend door actuator, and testing for voltage. If you are going that far, pull the actuator, check the door for non-binding operation. If the door is cool and you have voltage at the connector for the actuator motor, then, the actuator motor is bad.

 

Pretty common for the motor to be bad.

 

https://www.rockauto.com/en/catalog/chevrolet,2001,silverado+1500,5.3l+v8,1371507,heat+&+air+conditioning,heater+blend+door+actuator,10721

 

I have used the doorman part on half a dozen of these generation trucks with no comebacks/issues.

Posted

2001 Silverado 5.3. Compressor comes on and stays on. The line going from the compressor to the drier is ice cold and so is the high side line. AC worked fine last summer, heat worked great all winter and now it won't blow cold air. Any suggestions ? I don't have any gauges but can get some if need be.

My 03 did the same thing. Took it to the dealer and they said it was the actuator. Died in the middle of summer.

Posted

Thank you the help is greatly appreciated. I will have to check it in the next couple of days.

 

I personally would buy the actuator and have it on hand when you get to checking it.

 

If that door is binding, you will have do go deep in the dash to fix it. At that point, replacing the actuator makes sense as if the door is binding (not a common problem) that actuator is gonna fail soon anyway. They fail with a perfectly fine working door often enough...

Posted

Hi, new member here. I just had this same problem, we're going to try and fix it Sunday... any advice as to how to get to the actuator? We've already replaced the blower motor module because the fan speeds weren't working. Thanks!

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