is this normal?

[Y2KpewterZ]

So i was under the hood checking the trans fluid (which there was not any fluid on the dip stick, even though it was in the shop in may for a trans filter and fluid change) but thats not the question at hand.

What im interested in knowing is why my AC compressor keeps cycling on and off, even when the heat is on full blast (such as the case tonight, I had the heat on while it was running so i could check the trans fluid) The lines, I guess its the high side, which ever end has the recharge port on, is cold and frosty, as it should be with the AC on.

The controls on the dash seem to operate alright, except the speed is controll is out of wack (i.e. fan only works on low and high, unless i switch it all the way off and go right to the second or third speed, otherwise they wont work) i dont think this would cause the a/c compressor to cycle with the heat on.

And yes, even with the heat on the air still blows hot, and cold with the a/c on. Like it should. I checked the freeon and it is within range on the gauge that comes with the recharge cans yu can buy at advance or autozone.

Any ideas folks?

 

[97Tahoe2d4x]

I believe AC circuit is activated in defrost mode to give it "dry air" to aid in clearing moisture on inside of windshield. There might be some sort of short going on where your AC circuit is activated no matter where the air selector is pointed, especially since you mentioned fan speed control is out of whack.

That's where I'd start looking.

Peace!

 

[Y2KpewterZ]

Thank you for the input, as that seems what it is. Last night when i noticed i had heat on the floor and defrost on. Tonight as i was sitting in the drive through checking this thread I flicked it to heat on floor only and i heard the compressor kick off (as i had defrost on, and the compressor just happened to be cycling) and havent heard it click back on. So i guess this is normal. Thank you for clarifying this for me.

 

[BRUTUS_T_HOG]

Totally normal. A/C is on with defrost

 

[97Tahoe2d4x]

Thank you for the input, as that seems what it is. Last night when i noticed i had heat on the floor and defrost on. Tonight as i was sitting in the drive through checking this thread I flicked it to heat on floor only and i heard the compressor kick off (as i had defrost on, and the compressor just happened to be cycling) and havent heard it click back on. So i guess this is normal. Thank you for clarifying this for me.

No worries, it's perfectly normal for the AC to kick on with defrost.

Sure glad that's all it was and not having to chase electrical demons!

Have a good one!

 

[SunlitComet]

I wish they would have made it selectable to have the compressor run in defrost. Some vehicles do, some don't.