Rep Power: 0

found out the my radiator fan is not coming on when i turn on the ac and also i never hear it come on anymore at all. so my car has been overheating and i was wondering what i should do to fix this overheating problem. how do i check to see if its the fans fuse, the thermostat, or the fan itself. and can someone tell me the process of "jumping" the fan to start. I heard that i can just jump the fan to a battery source to check to see if it still works.

 
Rep Power: 300

Crank on the A/C and hold your rev's at 3000 once car is fully warmed up. If the fans dont come on within 2-3 minutes, Very good chance your fan/fuse is not working properly.

 
Rep Power: 454

First things first. Check the fuse. If that is ok, then check the fan motor.

 
Rep Power: 324

and if thats ok replace the fan switch.

 
Rep Power: 304

I doubt it's the fan(S) since there are 2 of them. 2 motors don't die at the same time. Check the fuse, and then try the temp sending unit that tells the ecu when to tun on the fans. There are 2 relays, the regular fan relay, and the AC fan relay that turns BOTH fans on.
If you can't find the problem, I can look in the service manual for you.

 
Rep Power: 0

I have a 2005 civic I had the timing belt and water pump replaced last month, after driving it about 1000 miles, I was on the highway I turned on the heater and the temp started to get hot almost to the max. I turned off the heater and the temp went back down. About 2 weeks later I was ideling parked and the same thing happened, once I turned off the A/C the temp went back to normal. I always have the a/c on but it only happened twice. I drive alot about 160 miles a day. I have checked the fans and they both turn on when I turn the A/C on, is thier a relay that could be going bad and failing intermitently? The car has 205,000 miles. What could be causing this?