cooling fan problem

Hello Everyone Again,

My cooling fans do not come on. I did some research after checking the fuses and relays and learned that my coolant temperature sensor could be bad. I read that a way to test this is to unplug the sensor, and if the fans come on, then I need to replace the sensor. Well, I did this and sure enough the fans came on. Unfortunatly, when I replaced the sensor, it still does the same thing. If the sensor is plugged in, the fans will not come on at all, and if the sensor is unplugged, the fans will constantly run. The wire appears to be fine, and I am wondering if the new sensor I bought from Autozone is bad, but I hoped that one of you might have some other idea for me to try. Another problem that started as well is that my A/C compressor is not engaging and giving me cold air. I put some more Freon in, and still nothing. Is it possible that these problems are somehow related? Any ideas???????????

I forgot to mention that I have a 99 Intrigue with a 3.5L engine.

What are your outside temperatures in your location?

Do you have digital climate control? If so, is the external temperature accurate?

Those have to do with your AC compressor.

As for the fans...you may be onto something with the sensor, with it plugged in what does your instrument cluster show temp-wise? Is it accurate?

I beleive that Harmonkardon35, or someone from the Toronto area had a similar problem with their vehicle, however they put in a manual switch to turn on the fans. Do a search, the post is no older than 2 to 3 months. Just be careful because you can get into trouble by replying to a post that is more than 3 months old, even though it could be a relevant problem.

I am in Dallas, and the temps have been in the 60s and 70s. I do have digital climate control, and I have it both cranked down to 60. My instrument cluster shows my gage to be right where it needs to be, which is slightly below the half way mark. When I unplug my sensor and the fans do not work, if I am stopped or in slow moving traffic, my gage will raise to slightly above the half way mark.
A little more history- I just replaced the engine on my car. My A/C was working just fine before hand except for the all too prevelent problem of blowing hot on the driver side from time to time. I did not have to undo anything regarding my A/C compressor other than unbolt it and keep it to the side out of the way of me raising and lowering my engine. The odd thing about my engine running hot is that it was doing the exact same thing when my other engine started knocking(the reason I replaced the engine). I believe the engine getting too hot in slow traffic during the summer is what caused the eventual breakdown. The thing I do not know is if my fans were working or not at that time. I remember they were, but I could not swear on it. I had to replace the water pump at the beginning of the summer, and it seem to start getting a little hot not long after that. I figured when I installed the new engine, that this problem of getting too hot would go away- how I am having the same problem really is throwing me for a loop. As for the A/C, I have not had the opportunity to do much trouble shooting other than giving it freon and checking the relays, and of course the electrical plug- to make sure I plugged it back in right.

I read the post about the manual switch- I may go that route, but I would much rather find and fix this problem if possible. Thanks

I have not had my Intrigue long enough to have had any major problems yet, plus, I only have 36,000 kilometres on it, so at the moment I am not expecting anything major with it. With that said, I haven't dug into anything as the cooling fans. I do know they run on two speeds though, I found this out by running the car with the hood open and ac on one day about a month and a half ago. The fans were on and then whamo, they came on like a hurricane for a short while. They then slowed down to slow speed. I shut off the AC and they turned off completely.

The only problem I do have at the moment is this stupid emissions air pump that makes a nasty vacuum cleaner sound at startup.

I would suggest just digging into the electrical system first. Try jumping the fans to see if they come on. Then go back to the relays and jump the connections there to see if they come on. Basically reverse process of elimination.