Nissan Repair: 1992 Nissan Maxima Overheating, nissan maxima, temperature gauge

Question
I think someone up here has the same problem I have, but when I'm driving my
car for awhile it's fine, but when i come to a stop for awhile, or put my car in
park with it still running it overheats. I think it's the fan to, but I'm not sure.
When I notice my temperature gauge moving to the H, I turn on the AC and it
goes down. So if anyone could help me please let me know.

Answer
Peter,

You answered the question when you said turning the AC on cooled the engine down.  If you have the car at operation temperature, with the AC off, the fan does not run.  Then turn the AC on and see if both fans run.  If both do replace the relay for the engine fan.  If not replace the fan that is not running.