Air Conditioning Issue

[DMAXNAZ]

Something weird just started. If I turn the temp to 68* or lower, it blows super cold. If I turn it to 70* or higher it blows at 100* or more.. The outside air temp today was around 50. I wouldnt think that should matter, but I figured I would share it just in case it might be part of the problem. What is causing this? I can't get a comfortable temp in the truck. Any ideas?

[DMAXNAZ]

So the outside temp today was 65*. I was able to turn the temp up to 75* before the heat would start kicking out. As soon as I turn it to 76* it blows at 135*. Below that the temp blowing out was close to the set point. I'm beginning to think this might possibly be a normal function. Can somebody else try theirs and see what happens? I'm pretty sure outside air temperature has something to do with it.

[bobsiding]

I have a 17 hd gas and mine wont hold a steady temp. it blow cold air below 69. to get it to blow warm air you have to turn it past 74. is there any service bulletin on this.  ive got a Colorado with everything manual and its easier to control the heat than this new and improved model

[DMAXNAZ]

Took it to the dealer. There was a SB, but not for that particular issue. They did the update anyways. They tested the system and produced the same results as me. When cold air was blowing it was pretty accurate, but when the heat came out it was all or nothing. 

[bobsiding]

what did the dealer do? did they fix it? or do you have to live with it?

[DMAXNAZ]

There was nothing they could do except the sb.