coyote121403

So an update / background: When I'm driving around town and the temp gets over 210 the jeep dies, I have to wait 15-20 mins then it runs again. If I'm driving down the highway its fine, temp stays just under 210 and jeep stays running. I found out the aux fan is not working at all. I swapped the relays from the AC (its the same relay) and still no go but my AC doesn't work anyways so no telling if that relay is good. Here's the Q: How do I test a relay without buying a new one? (autozone said they couldn't test it). If the relay is good what's my next step? The fan thermostat control? I changed the head a few months ago and from what I recall it worked when we were done. Thats the last I remember it working.

kidkodiak

Have you tried testing power to the fan directly to see if it works at all? If the fan is completely dead regardless of the relay, then it's (theoretically) just a replacement part.

If it works when directly powered but none of the rest of the time, then maybe it's the relay or the coolant temp sending unit.

coyote121403

Thanks. I'm gonna grab a light tester and see if I can get in there when it's hot and see if there is power going to it at the connector to the fan. Is that how I should check it?

dyte2004

just take two small bits of wire and jumper the connector one wire to ground the other to positive termanal of battery

coyote121403

Ah, that sounds easier. Thanks.

Abovetimberline

you said your ac is not working,if it is low on freon the electric fan will not come on,the circuit is wired to come on when a/c is turned on and when temp reaches a predetermed set point 210-220 approx when car is below 35 mph. If your fan works when connected direct to the battery,then take the two wires going to the low pressure cutout located next to the comp and wire them together,this will make the electric fan think the charge in the a/c system is fine and the electric fan will start as needed.

coyote121403

Great info. My AC has not been converted and is dead empty. ( It has never worked since I've owned it) The shop wants $1000 to convert it so I can do without AC. And now that you mention it I think this started to occur after I had them check the AC. I wonder if they did something...

Abovetimberline

$1000 is a rip off,I converted mine for about $50,of course there were no leaks and everything worked

coyote121403

I am having trouble locating the 2 wires. Is it the 2 black ones on the left side of the comp. by the pully? Anyone got a pic or diagram?

coyote121403

nevermind. I looked up the part and its location on NAPA. Found it. Also I found a couple 12oz cans of R-12 on craigslist for $20. Should have the shop fill the AC up with it (it's illegal to do it yourself) and see if it holds and doesn't leak or just do the conversion and hope it works? Last question - how many cans of R-12 will the system hold, anyone know?

Abovetimberline

Looking from the passenger side fender you will see a sensor screwd in to suction line to compressor just cut the two wires and strip them back enough to conect them,all this does is bypass the switch. Leave enough wire to reconnect down the road. As far as converting your a/c to 134,that is easy as long as your system is tight,I know some may disagree but if you just go and get a recharge kit with the guages from your choice of stores and an extra can of freon,plus a can of charge oil for 134,you can do it your self,just follow the instructions,if the system has been opened up you will be wise to replace the receiver dryer also because the desicant will be used. I have done this many times and never had a problem.
If you take it to a shop they will draw it down and hold it a vacuum for 30 minutes to insure there is no leaks,then they may or may not change the seals,and recharge it,that's it,you are paying for labor. I am not sure where you live but with july half gone maybe it can wait,unless you are in the southwest. as far as cans,2-3

coyote121403

Thanks again for the info. From what my mechanic said the system might have been open for a long time. Autozone has a reciever/drier for $30. I guess while I'm in there I might aswell get an AC O ring kit, take it apart, clean everything thoroughly and throw the conversion kit on it. Hopefully the condensor and comp. are still good. I really can deal without AC but my 4 and 5 year old seem to disagree... Eventually this jeep will have all new parts

Abovetimberline

You will know right away if the comp is working if the guage is hooked up,actually when you replace the seals just check the comp at that time seeings as the suction is already open. with the suction valve open you can actually here it running.

95cherokeesdc

mine didnt work either couldnt figure out what it was so i straight wired it to a toggle inside the cab

coyote121403

It worked. I spliced them together and it comes on but the jeep still gets around 220 and shuts off. I might toggle it later on. I'm replacing the CPS and putting a 180 thermostat in it tonight. Just going with the 180 because I'm pulling my boat around alot for the summer. I'm thinking next year I might need to buy a grand cherokee or a F-150 to pull that thing. The jeep is light and scary on downgrades in the mountains. Or maybe put a big brake system on it.