I have an 07 RDX with about 68k on it and I am having intermittent a/c issues. Periodically my a/c will start blowing warm air. Sometimes it happens after driving for a while on the highway or in stop and go traffic. Yesterday it happened as soon as I started the car. Sometimes if I turn the a/c off and back on it will start blowing cold again as though nothing is wrong. Sometimes it will keep blowing warm air.

It doesn't appear that the unit is icing over since when it happened yesterday it happened as soon as I started the car and the car had been sitting over night. The fans are functioning properly and I had my mechanic check the refrigerant levels and everything was within normal range. When he looked at it he said if he didn't know better he'd think everything was operating normally and of course the problem did not happen while I was there.

Any ideas?

 

when it starts blowing warm air do the fans come on? and does the clutch engage when it blows warm air?

 

I do hear the fans under the hood continue to cycle normally. I have not been able to hear whether or not the a/c clutch is engaging. When the mechanic checked it he said the pressure was in range and the system was cycling normally but unfortunately it never happened when I was there.

I can tell you that it happened to me 4 times this morning while doing 75 on the highway. Then mid-day on the same highway in a higher temperature at about the same speed I had no problems with it.