Light

I normally do I searched to find an answer first and got nothing to help me out. Probably worded wrong to get a good hit on the search.
Anyway, I have 2001 JK with the 4.0L for about 2 years now and NEVER have I heard the electric cooling fan running the whole time I have had this Jeep unless the temperature reached above 100C
The other day I was coming home and noticed the sounds of the electric fan while stopped at a traffic light. First thing I do is check my gauge to see if I am overheating. Of course I am in the good, about 90C*.
I get home and park the Jeep, I let it sit for about an hour i switched off the ignition and the fan stopped. I turn the key on the next day to check my temperature gauge and it reads about 0C so normally the fan shouldn't work but when i start the ignition the coolant fan start working Engine is nice and cool but fan is still running. so I guess I will disconnect it till I find out what is causing it to run.

Firehawk068

If you have your heater/AC controls in any of the positions that cycles the A/C compressor on (windshield defrost setting), the electric fan will turn on also...................

I also thought the 4.0 ended with the TJ? I didn't think they made a JK with a 4.0?
Here in the States, we didn't get the JK until 2007..............with a 3.8 engine.

Light

Thanx will check that and let you know i meant XJ lol

djb383

On '00/'01 XJs the efan does not immediately turn on when the compressor engages.....only '99 down efans turn on immediately when the compressor engages. '00/'01 XJ efan turn on when refrigerant reach X pressure and/or coolant temp reaches X temp. Your '01 JK may function the same and needs some investigation.

Light

i guess so because i already checked the other part, so where should i start investigation?

Light

i checked the parts that you told me and its all off so where should i looking?

freegdr

Sounds like possibly stuck cooling fan relay.

Light

Might be but where is the relay located?

Firehawk068

Yes, sounds like the relay for the fan is stuck....................
Most of the relays in the power panel are the same, so you could swap them around before buying a new one.

freegdr

Google it ...

SteveMongr

On my 1996, the e-fan is also controlled by the 'coolant temperature sender'. This sender has caused the e-fan to turn on after a cold start.

CCKen

In the Power Distribution Center (PDC), black box on the right side of the engine compartment.

Here's the layout.

There's no other relay you can swap with the radiator fan relay, other than the ASD relay. If you swap these two and the radiator fan relay is defective the engine won't start.




.

CCKen

Here are the operating parameters of your radiator electric cooling fan - from the 2000 XJ FSM:

Electric cooling fan 4.0L: With or without A/C request the electric fan will come on only when the coolant temperature is at least 106° C (223° F), and will remain on until the coolant temperature drops to 103° C (217° F) or below. Regardless of coolant temperature, When air conditioning system pressures reach 2068.5 +/-138 kPa (300 +/-20 psi) the electric fan will engage and continue to run until the A/C system pressure drops to 1620.3 kPa (235 psi) minimum, then the electric fan will shut off.

CCKen

Here's a functional schematic of the 2000 & 2001 AC Switching system.



.

Light

Thank you for your information it really helped i switched the relay but it the same thing now the fan is turning on and off on off on off on off and some time it keeps on the whole day and its keep doing for a while even the temperature is low will am lost