#2 Cooling Fan

I just bought a 99 alero gl coupe,3.4 v6,so i decided to clean her up.I washed the motor with a pressure washer .Later on that night a few hours later i noticed that the #2 cooling fan was running and wouldnt shut off.I then pulled the relay out so the battery wouldnt go dead.The fan goes off when you turn the ignition on but comes back on when you take the key out.Ive switched relays with same result.Sometimes it comes on and goes right off and comes back on,15 min could go by and then it kicks on.Is water possible cause for this.Everything else is fine temp gauge works properly,both fans come on when ac is on.Please advise Thanks

Welcome to AF.

Sounds like a possible short which could be due to moisture. The cooling fan relays are hot at all times on one side of the coil. So if the relay input which comes from the PCM module is shorted the respective fan will run. The relay has to be energized to turn the fan on. An area of concern would be the engine compartment fuse box. Check there for water and try drying it out since the cooling fan relays are located there.

Thank You bnaylor for you response,I think thats just what happened.Just before I left for work I opened the hood and let it get some sun all day.When i came home I put the relay back in and it hasnt come on yet. Thanks again

Thank You bnaylor for you response,I think thats just what happened.Just before I left for work I opened the hood and let it get some sun all day.When i came home I put the relay back in and it hasnt come on yet. Thanks again

You are welcome. I'm glad it worked out for you. The engine compartment fuse box is defintely not an engineering marvel. The location is alright but it should have been installed at an angle instead of flat. A lot of known issues with it.