Why didn't you ask the mechanic? Assuming nothing is actually broken,
evap freezups can be caused by having a low refrigerant level. Any
competent AC shop, or even a gas station doing simple AC work, can
check for leaks and top up the system if there are not any large
leaks. You could easily have lost enough refrigerant in 15 years to
need a top up and nothing else.
Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here.
All logos and trade names are the property of their respective owners.