my fan will not come on but does work when i put 12v to it and the relay is good also the car does not get hot it stays air cooled pretty good i think it might be a sensor some one let me know which one it is
The coolant temp sensor is the one that tells the fans when to come on. But the main fan doesn't come on until 212F. So if you are in a cold climate or driving on the highway, the fans may not run because they are not needed. If you have access to a scan tool, some of them will tell you if the fan is supposed to be running.
Go and get a temp sensor. Cheap and easy to replace. Maybe 10 bucks or less and they usually come with thread sealer already on them. If not be sure and use teflon thread tape.
i'm experiencing the same issue. my fan does come on when my a/c is on but other than that it doesnt engage. the temp sensor is good. i bypassed it by unhooking the wires and putting a paperclip in there, the guage went up to 260 and the fan still didnt engage. any ideas?
The ECU is what tells the fan to come on. From the factory they are programed not to come on until 223 degree's.
If the car is not running that warm no issues.
If it is, then check grounds. My 96 had that problem. Ended up running a switch to turn the fan on when I wanted to.
FU Tuning
The fan on our cars does not run much. In the South here it doesn't come on all winter unless I have defrost on. Even in the summer when I don't have the AC on and I'm not in stop and go traffic it doesn't come on. Don't look for it to come on, if your temp gauge is working then it's something between the BCM and fan. As long as the temp gauge doesn't hit the top then it's fine.
I am tempted to get a fan over-ride switch. Sometimes my car seems to hold out a little too long before activating or disengages a little early. Sounds like a win-win to me.
My wife's 2003 Ecotec 2.2 liter Sunfire:
* 2 1/4 inch in and dual 2 inch out muffler Trans Am muffler
* 2 1/4 piping to a very long 2 1/4 inch resonator
* 2 1/4 inch catalytic converter
* an AEM true cold air intake NOPI edition
* 8 gauge ground wire kit
* Toyz front strut brace
* Russell stainless steel brake lines all around.
