aux fan doesn't come on after 210. no ac system

so i'm pretty stumped at this point. ever since i bought the jeep the e fan never turned on. at first it was disconnected so i connected it and nothing. the fan works and right now i have it powered on a switch just in case. when the temp gets past 210 it doesn't come on. the jeep doesn't have an ac pump because it seized up on the p/o instead it has a bypass pulley. i don't know if that has anything to do with it. the moment i pull the plug at the temp sensor, the fan turns on. the sensor is an oem mopar unit. I've already checked the temp with a probe and i let the engine get as hot as 220* but it still doesn't turn on. any advice?
btw it's a 95 4.0

at least on 97+ the e-fan turns on at 218*F or when the A/C is on. I was having fuel injector issues because of the heat so I wired in a 5 post relay and a painless temp switch. This allows the fan to act as it would from the factory (avoids ecm codes) and turns it on at a lower temp.

On a '95 it should also be 218*. This was the case on my '96. The defroster will also engage the fan, so try that. If that doesn't do it (sounds like it most likely won't), then I'd replace that temp sensor. If the defroster makes it go on, then it's a wiring issue or unlikely ECM issue.

vt98xj said:

at least on 97+ the e-fan turns on at 218*F or when the A/C is on. I was having fuel injector issues because of the heat so I wired in a 5 post relay and a painless temp switch. This allows the fan to act as it would from the factory (avoids ecm codes) and turns it on at a lower temp.

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i was thinking of something like that but i want it to function just like it did when it was new.

Planetcat said:

On a '95 it should also be 218*. This was the case on my '96. The defroster will also engage the fan, so try that. If that doesn't do it (sounds like it most likely won't), then I'd replace that temp sensor. If the defroster makes it go on, then it's a wiring issue or unlikely ECM issue.

Click to expand...

just tried that but no dice. it sounds like the sensor isn't reading correctly but, it's a brand new mopar piece. my last piece was one from autozone and it did the same thing plus, i didn't trust it, that's why i changed it. i'm going to try to find the one that came with the jeep which looked like the original piece. i'll keep you guys posted