StevenGilroy

My 96 C2, has always had great A/C and heat, except for two times recently. I parked the car for a couple hours in the sun, 96-98 degrees outside, inside got to maybe 140+. Started the car. turned the A/C on and rolled down the windows to let some of the heat out, no A/C just air. Started for home, and about 20 minutes into the drive the A/C came on. The temp readout was showing 94 outside. Can high cabin temps affect the A/C control unit? The second time was even hotter, parked in semi shade but it was 102, same thing, the compressor clutch was not working. Came on again as them showed 96. Once home I checked the fuse, wire connection and relay did not see any issues. So far I've driven in 100 degree heat, A/C worked well, but the interior was cool, went from cool garage to foggy ocean, just about 30 miles in the heat.
Any ideas? Thanks Steve

paranoidandroid

My guess is leaks..the pressure switch might be kicking in to cut power to the compressor, but likely this will get to a point where the compressor clutch never engages. Buy a blacklight and check for UV dye. Common places are: evaporator (check UV dye at the drain or in the suitcase), compressor itself (check for oil under the compressor) or the condensor (use a sniffer).

OP's first post is GOLD. Follow that.

StevenGilroy

I did a check of the Freon and it's all good, I had it all serviced last year, it's only when parked in the extreme heat that it fails to engage the clutch. Just now drove home and the A/C worked well, it's 82 outside and I put thermometer inside and it was 104-105. I think it might be something in CCU fan or inside temp sensor not liking 140+ degrees. It's. suppose to be only in the 80s for the next week, which is pleasant, and we will be spending most of it in Monterey, Car Week!!!

paranoidandroid

pull out the CCU and clean the it. You might find a giant dust ball on the cabin air temp sensor that is throwing off temps. https://www.bergvillfx.com/categorie...93-ccu-details

StevenGilroy

I will do that, thanks for the tip.

jackdfitch

I have the same problem AC work fine with fan on max but can't if not on max fan just runs very slow. Also condenser fan only runs on fast not sure they are related, I'm guessing the resistor is bad on AC side
Just replaced resistor on oil cooler

1997hmc993

This is one of the best AC service reading I ever done!
Thank you.
By the way, my problem was compressor power plug not properly connected after I replaced belts. So it was solved on your 1st step!