Subaru Repair: fan speed changes, subaru legacy, long distances

Question
I have a 1997 Subaru Legacy w/2.2 engine. When I have the AC on and the fan on maximum, and accelerate, the fan slows down noticably.Also the lights pulse when driving long distances at night . Autozone checked the alternator and it was fine.Any help would be appreciated

Answer
Have the alternator checked somewhere else.By someone who knows Subaru.At our shop we see a lot of problems go undiagnosed by people not familiar with the product.On that year Subaru the best way to test the alternator is to start it up ,turn on all accessories ,lights radio ac etc.make sure the hood is shut and run it for 1/2 hour minimum then test the alternator.Heat increases resistance and will expose parts that work ok when cool.

Justin
All Wheel Drive Auto