AC won't work when outside temperature is high

[Hoosier716]

My 2006 Maxda 3 has an intermittent problem with the AC. When it is cool outside (in the early morning) the AC blows cold air, but when the temperature heats up it only blows warm air. My mechanic has checked all parts and components on the HVAC system and assures me it all checks out. His best guess is it is an electrical ground issue of some kind.

Anyone else experienced this problem?

 

[philrab]

You need to find another mechanic.

There are a dozen reasons I can think of to cause a situation like this, and unless you have some kind of mechanical background there's really no way for you to diagnose it yourself. I've R&R'd most of the AC in my 2007, and it was a trying job (I have a mechanical background in cars and aircraft).