jeepbro1xj

Hello,

I live in Alaska, and as you may know, it is very cold up here. I recently have been having troubles with my electric radiator fan not turning off when the car is turned off. These problems have started since this winter. I typically use the heater on full blast just as a defroster for the windows, but I wasn't sure if that would cause the coolant temperature to rise or not. Sometimes this problem persists, other times the fan goes off with the car.

This morning I came back to my car with a dead battery because the fan kept running, and when I went to jump the car (30 degrees outside) the electric fan jumped on immediately. The fan was running even though it was freezing outside.

So I am wondering if you out there think that this is a relay problem, or maybe a temperature sensor problem?

Lastly, I have found a very small and slow coolant leak underneath what i believe would be the water pump. Could this be the cause of the overheating if the coolant is not pumping through enough?

I believe that the two may be related, but are more likely just having their own issues at the same time.

Thanks, and I appreciate any help you can offer.

My car is a 1998 Jeep Cherokee XJ with 4.0L

Firestorm500

You could unplug the auxiliary fan for now. Then fix the water pump.

Work on the fan when it warms up some.

You said something about a water pump drip causing overheating. Is it or is it not overheating?

jeepbro1xj

Firestorm500,

I believe that it is a separate issue. It is hard to tell if the temperature is raising because I dont have a gauge, I just have a light that comes on if it is overheating (if it even works), which it hasnt come on yet. I believe that I have two different issues, but I am not totally sure if they are related...

1. The electric radiator fan was on even though the car sat outside in the cold weather overnight.

2. And I noticed a little bit of coolant leaking from what could be the water pump

And then a final question... would the electric radiator fan run if I was running the heat in the car?

Thanks firestorm, I appreciate your help.

CCKen

AK,

Go to your Power Distribution Center (PDC) in the engine compartment and remove its cover. The relays are identified on the cover.

Pull the radiator fan relay to see if the fan stops running with everything off. You might think about replacing that relay if it does.

jeepbro1xj

CCKen

I pulled the fuse for the radiator fan and it did turn off. This would be indicative of the fan relay getting stuck or is damaged?

Thanks

freegdr

No that just killed the power to it replace the fuse and pull the relay as stated above. And yes fan will run when heats on.....

Firestorm500

Really? Even in 30 degree weather? No engine overheat?

exjay1027

you probably dont even need that fan up there. i ditched mine a year ago and i havent gone a degree over 210 since.

and your water pump most likely needs to be replaced

nicksan

Cant you just wire in a manual switch mounted on the dash somewhere to control it?

jeepbro1xj

Hello,

I appreciate all of your help so far.

So I got back to my car after work, and I plugged the fuse and the fan started right up on cue. I went for the relay to unplug it as recommended, and as soon as I touched it, the fan turned off. Would this indicate a faulty relay?

Also is it typical for this vehicle to start having a ton of problems around 120k miles? Because after my car died because the fan kept running till the battery was dead, I tried jumping it, and I got plenty of charge, but the car was not turning over.

I am sorry that I am such a newbie.

Firestorm500

A completely dead battery, in cold weather, may have to sit with cables on or on a charger for awhile before it can turn over an engine.

If you can plug it into a slow charger overnight, that will help top it off. Some people say an alternator will not charge a completely dead battery like a generator does.

Supposedly, an alternator is just supposed to maintain a charge.

Don't worry about being a newbie. All of us here were newbies at one point. We're here to help.

freegdr

When heats/defrost on ac compressor cycles so fan will also

sounds like sticking relay.

CCKen

More than likely.

Before installing the new relay, check the pins on the old relay for corrosion, and verify that the pin cavities in the relay socket are free from corrosion. Corrosion can look black, green, or dark gray.

djb383

On a '98 XJ (I presume other years as well) the vent selector ****'s position (not the temp ****/lever) is what determines when the a/c compressor is engaged.....when the compressor is engaged, the efan is on ('99 down). There r 5 vent selector positions (yellow circles) that engage the compressor AND efan and 2 positions that don't (engage the compressor or efan).

Firestorm500

To my knowledge, an A/C compressor does not engage below 40 degrees F ambient temperature no matter what position the *****/selectors are in.

Which is where my question came from concerning continuous efan running at 30*F ambient. Even with key off.