Update: In time, I've noticed my glovebox, tailgate, and windshield washer would fail to operate whenever I had the AC issue.

I ended up replacing the JBE module with a used one and coded it to the car. All components including the AC are working flawlessly.

Well done for sorting your problem. When they diagnosed my problem after re-gassing etc the fault code was internal temperature sensor fault, don't remember the actual code. Still haven't got to the bottom of it and we are heading across Europe again next month.

Hopefully your problem is a simple sensor swap.

I'm still learning how to use ISTA and wasn't sure how to troubleshoot. Ended up bring the car to the dealer for diagnostic.($180) They quoted $1,200 to replace the JBE so they can do further testing. Since the JBE is fairly accessible, I declined the repair.