99 aux cooling fan

After nursing my a/c for two years and reading all the threads on a/c problems I took my 99 7.4l sub to a shop to have the leak in my a/c fixed and the freon properly serviced. They replaced both rear lines and the evaporator, the high pressure switch,and serviced it. The a/c works fine now but the aux cooling fan is running all the time. Before the fan never ran. I jumpered the a/c compressor relay last year, so I knew the fan was good, but I never went any farther than that. I was poking around tonight, and I can't find the aux fan relay. Any info would be most helpful.