anojes

My 2000 Sport won't turn the auxiliary fan on when I turn the a/c on. The fan has power and the temperature gauge works. Any ideas?

dyte2004

is the ac engaging there is a low pressure switch for the ac gas if there is no gas or low gas the whole ac shuts down including the fan

STROMVADER

x2 or your fan could be cooked. I just replaced mine a 1/2 hour ago. If you have alligator clips and some extra wire, you could jump the fan plug to the battery.....just watch your fingers! A new fan from advance is 100 bones.

anojes

If I unplug the fan switch on the thermostat housing the fan turns on. And my a/c works great. That's why I'm stumped.

dyte2004

doing this should cause the engine check light to come on as the ecu thinks there is a fault fan comes on in short burst am i correct

anojes

Yes, the check engine light comes on. I would like the fan to start when I start the a/c. My rig gets hot in traffic because the aux fan is not starting

dyte2004

you can always wire the fan to a switch

anojes

I know, I just don't want to add another switch inside the cabin. That's why I am trying to get to work like when it came from the factory. But thanks man.

anojes

I still have not foud the answer to my aux fan turning on when I turn on the a/c?

SeniorXJ

Open up your fuse box under the hood,, read the discription of where each relay is,, pull it,, then go get a MATCHING new relay. Make sure you go 2 the parts dept & have the dude look it up on the computer because the off the shelf ones wont work no matter what anyone says.
((then again, i drive a 95 & urs is a 00 i believe)).

Oh and i just went thru this situation myself,, except my solution was an override in cabin switch. Now i can turn it on & off when i want!! Its such a GOOD mod and very easy to do,, flip that pupy on and she wont go over the half way mark!! I just bought a new 180 deg stat so hopefully that will help it drop some more.

Hope that helps!

anojes

So you think that the fan relay is what is avoiding tha fan to turn on when I turn on the a/c?

SeniorXJ

YUP! If the relay is no good then theres nothing to signal the fan to turn on.

I decided to say screw the stock relay cause my AC doesnt work anyways, and so i found a GOOD right-up on a wire diagram for the in cab override switch. Its very easy, and if your a real XJ driver then im sure u have a habbit of watching ur temp guage like a hawk! Now i control the fan!!

a1racer

my 2000 does the same but it will turn on if the rad gets over 210 so i was wondering the same but i think i will just do the switch mod and wire it to an ignition source so it wont stay on if i forget to turn it off

anojes

[quote=SeniorXJ;216610]YUP! If the relay is no good then theres nothing to signal the fan to turn on.


I thought that if the fan realy was bad the fan would'nt start at all?? The fan goes on when I reach about 220 but here in Puerto Rico it's hot all year long, so the a/c is on everyday and as soon as I park it I hear the radiator bubbling.

SeniorXJ

[quote=anojes;216643]If i were you,, pick a day when ur drivin around alot with your AC blaring and when you see that temp guage start moving towards the 220 mark,,, pull over,, leave the jeep running,, pop the hood and physically see if your aux fan is on!!!
Trust me, u have no idea how many times i told someone to do that and BAM, its NOT on!! NOTE, this doesnt mean the fan itself is bad which is why i say to checkout the relay.

Another test you can do is have a friend who has the same make model and year jeep who has a working system,, take his relay out and put it in ur relay spot. That should tell ya right away what the issue is. JUST MAKE sure his works,, and make sure ur engine temp is high when u put it in, then go turn the ac on.

What year & model XJ is this??