A/C comes on by itself

[caddibear]

I have a 1999 Chevy Silverado 5.3L.

Recently the a/c came on by itself and would not turn off. We almost froze on the hour ride home. Two days later started it up and was able to turn ty heat on. 

Can someone please let me know what to do or replace. Do you think it might be the heat / Air control switchs? I looked that up on YouTube and think I could do that myself, if you think that's the problem.

[91 Shortbed Chevy]

On 12/3/2019 at 12:19 PM, caddibear said:

I have a 1999 Chevy Silverado 5.3L.

Recently the a/c came on by itself and would not turn off. We almost froze on the hour ride home. Two days later started it up and was able to turn ty heat on. 

Can someone please let me know what to do or replace. Do you think it might be the heat / Air control switchs? I looked that up on YouTube and think I could do that myself, if you think that's the problem.

That's the first thing I would try. It's the only thing that makes sense this early in the morning.