Key hot only.

Power all the time I think.

Temp sensor as it gets hot, it drops its resistance and goes toward zero resistance. The temp sensor then becomes the ground if I remember right.

I actually...now thinking about it...I can't remember what the wires show. I just remember the temp sensor becomes a Pass Through with zero resistance between the two wires. So I attached the switch to the two wires and it basically by-passed the sensor and ran in parrell.

This allowed the sensor to still kick the fan on AND allowed me to override the system and kick the fan on myself if I wanted it.

I know I have some wild setup from becool on my CJ7. Basically the fan will run even with the key off...cooling the radiator till its below 160 degrees. The CJ also has a kill switch to turn off the fan for water crossing. The last thing I haven't installed yet was a timer relay to reset the OFF switch after 5 minutes incase I forgot to turn on the fan.

What I really want is a Low= off, High=ON and 240 degree=emergency ON. That way if I have the switch off for water crossing, if the engine hits 240 degree, the fan will come on regardless.

 

Coming on in the water might not be a good idea. Sounds like a good concept though. Just needs a master OFF switch for those water crossings.

 

I need to get my server back online...I have a ton of tech data on there.

Whoever the powers may be here...I can send a bunch to you and you decide what you want to post and what not to.

Many things are PDF prints of other forums listing tech that is very useful.

 

If it is copyrighted then it can't be posted on Cf, at least that is my understanding. Kyle would know the exact specifics on this.

 

Okay... I snapped a few pics of mine... they aren't great..

But this the factory fan relay.. its behind the air box near the ballast resistor and the vacuum selenoid(for something I cant remember right now)



The red wire in the picture runs to the switch on the dash.

The red wire is scotch-locked to the orange wire out of the harness which goes to the switch side of relay. It provides low-amperage voltage to keep the high amperage side switched on.



Here is the switch. Its a basic parts store switch.. It has a green led on it, but IIRC it was only a 10 amp switch. Its wired into full-time power so I can operate the fan on really hot days to keep some air moving through the engine compartment even while parked on the trail.

 

Got a good coin collection going there too. Mine is a 90 too and I have no such relay under the hood where yours is. BTW that vacuum thing is part of the EGR valve.

 

Hmm... my 88 fleet XJ and of course this 90 Pioneer both had them. My 88 MJ custom base doesn't, but it wasn't equipped with an aux fan from the factory.

 

I forgot to ask this... what was your aux fan wired when you got the heep???

 

ok i tried this and it worked but my engine light came on. is there another way to do this without buying a relay? i have a 92xj btw.any help would be appreciated.

 

*dig up* would this work fer a 97+??

 

I know go jeep has a write up spme where on how to wire it correctly. his i believe was wired for all time on, with thermo switch, and off for water crossings. any way hes got good stuff so snoop around

ttp://www.go.jeep-xj.info/

 

hmm.... im lookin a diagram would be all i need... 3 prong switch and a relay

 

I have a 98 and i think i actually ended putting a 96- in mine cause mine went dead....had to rewire, but it works wonderful

 

do you have a switch that manually turns it on but when the switch is off it'll just be factory settings?

 

yup the fan is controlled via the computer pulling therelay or switching the earth seems to bring on the check light