Hey yall,
So I have two questions. One, check out these pictures. Can anyone tell me what this gray wire is? In the attachment, I have included a little arrow pointing to the wire Im talking about. Heres a link without the arrow for clarity.

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I noticed it because Im trying to track down the reason why my coolant fans only engage when the AC is on, when the SES light is on, or when I engage diagnostic mode. I disconnected all the ground wires and cleaned then up the other day, I also replaced both coolant fan relays in the fuse box as well as the fan/act fuse. I was tracing the ground wires running from the battery and couldnt find any issue up to where the wire bundle meets the left side of the radiator but I didnt have time to go any further. My AC recently sprung a crippling leak and I have noticed that if the car remains idle too long my temps will slowly climb. I read that it could potentially be an issue with the ground's on the car but I have ruled out almost everything else it could possibly be and on my next day off I was going to really dig into the wiring and see if I could spot the issue.

Any comments/suggestions would be much appreciated.

Edit: Oh and for the record, I have tried two different fan shrouds and replaced the water pump coolant temperature sensor AND pigtail recently. Problem persists and Im stumped.

 

What temp is it getting too? Fans don't kick on till 220F

 

Itll go all the way if I let it and still they wont come on. I will kill the engine if it gets that hot.. or if Im on the road, I can usually start moving and get the temp to drop back down to normal levels. Anything over about 45 mph and the temps stay consistent but anything less and I see a gradual rise. Going through a drive thru? Forget it, ill be about to hit the red by the time I get moving again.

Edit: See, I never fully address this problem before because in Florida.. my AC is on at all times. I took it to a shop a few months ago and they said "rebuild the ECU".. well that didnt fix the problem either even though I knew that it wouldnt fix the problem.. I figured well.. lets do it anyways. Now that the AC is out, Im really wanting to figure this out. So overall, Ive 1- replaced the fan, 2- replaced the relays, 3- replaced the fuse, 4- rebuilt the ECU, 5- cleaned the grounds and did a visual check of the connection and it appears to be fine. I think that really just leaves the wiring

 

So, were the fans working when your AC was working but now they don't come on anymore? Did your AC just run out of refrigerant or is there another problem with the AC? Try putting your rear defrost on, the fans usually kick in.

 

Coolant temp sensor could be an issue. There is one in the pump that gives info to the ECU to kick on the fans and one in the head for the gauge. Test before replacing as I don't remember them being cheap.

As far as the wire goes...hard to tell, but it looks like it's the A/C Evap temp sensor.

 

Well guys I have an update for you. The good news is.. I was wrong. My fans DO operate properly. I recently put a radiator flush in my car and drained it today and in the process of refilling it and bleeding the system.. I figured this would be a good time to take my infrared thermometer and let it get to 236 degrees and see what would happen. The odd thing is that 236 degrees according to my dash temp gage.. is basically the first red line while 226 degrees when they turned off is the line just before that. I pointed the thermometer directly at the temp sensor on the head and moved in between looking at the temp on that and the dash gage.. and they came on right at 236 and off right at 226. It just seems SO strange and almost wrong to have the fans operate with the gage on the dash basically maxed out. This is really a sigh of relief for me knowing that my car does in fact work right and that I dont have to worry about seeing that temp gage climb a little bit. 185-195 which is what I usually get while driving is about 2/5ths of the gage on the dash or roughly just under halfway to just over halfway.. so thats a pretty strange way of presenting the temperature to the driver. I kind of feel like an idiot now that everyone of you guys kept saying "they come on at 220-230" and I just could NOT accept that my stuff was working properly. Lol, thats why i love you guys. thanks mkcoco and everyone else!

 

I'm surprised yours even gets that hot. My Camaro takes forever to get to 190-200 range, while my Jeep will be at 210 in five minutes and it will stay right there regardless of the temps out side or if I'm idling or what, makes for good heat in the winter.

Glad we could help and glad the issue has been resolved.