2011 Yukon XL. A/C works great while traveling down highway, very cold. However, when sitting in parking lot or in line at drive through air vent temp climbs from a frosty 38-42 to 70-75. Not fun in traffic jams at 95 degrees, but also not a failure. Had the charge tested and system leak tested at shop. 3lbs, no leaks. Compressor pressures were in range. Used scan tool to activate low and high fans. Both work when activated. Replaced relays anyways, still work. Noticed that when idling in driveway in 93 degrees heat the high pressure climbs to just about 200 and kicks off. Drops to 175-180psi and kicks back on, kicks off again at 200psi, about 10 seconds later. Air temp from front vents cools down during the short pressurized cycle. It’s like it’s just not running long enough. I wish I could ‘tell’ the compressor to stay on longer. I think that would solve it. I even activated high speed fans with scan tool to see if it would help. Only minor improvement, don’t think it’s fan related. Is there a reset procedure or could the module be sending a signal to kick off too soon? Bad module? Something else? Engine coolant temp sensor was replaced last year. Says engine temp 196-200 while idling. Confused as to why system is turning off before it builds enough pressure. Did notice RPms dropping a little below 600. Could it be RPM related? Thanks for any help.