2002 jetta is overheating when i turn on the AC or when it idle's?

The other day i was sitting at a red light waiting to turn. I looked down at my temperature gage and it was rising. I pulled into the gas station and let my car sit for about 20 minutes. As soon as i got back on the road the temperature went down to 190. It seems to only overheat when im idling, ac is on. When im driving between 35-45 mph the temperature is fine. Also i had a friend check my fans. I turned my car on and neither fans turned on, also turned my AC on and neither fans kicked on either. Please help thanks!