Overheating !!!!!!!!!!!

[lilchas]

99' jeep grand 4.0 L radiator fan not turning on at all causing overheating. Checked fuses and replaced thremoswitch and thremostate , sill not running, please advise, Thanks.

[sreilly77]

Originally Posted by lilchas

99' jeep grand 4.0 L radiator fan not turning on at all causing overheating. Checked fuses and replaced thremoswitch and thremostate , sill not running, please advise, Thanks.

the motor on the fan might be shot itself. i had that problem with another car i used to have. it kept overheating because the fan wouldn't kick on but the relay was still good. turned out to be a bad motor for the fan so i replaced the entire fan assembly and everything worked out fine.

[dcx96]

B4 you go any futher go to the dealer and get a cooling fan relay that IS the problem it's located under the passenger side head lite you will have to get replacement rivets too because you will have to remove the fascia the grill and absorber and you will need a L shaped screwdriver (small) to remove the 2 screws that hold it in. Garunteed!! This is not by any means a hard job you can do it.

[lilchas]

Upon research found out it was the fan relay .Had to take pass. side headlight out ,only way to get at relay other than takiing whole front bumper off was to drill 2" hole in plastic under headlight to remove and replace relay , what a @#$^&(*%!. Working fine now.

[jonzi216]

I had the same problem last year(03' Grand Cherokee Loredo) and the Dealer charged me $260 bucz just to change the cooling fan relay..having the same problem again (fan not kicking on), so I found a new MOPAR relay on ebay for $30 bucks, and going to attempt to install myself. wish me luck!

[Bob D.]

Here is a how to on changing the module via the headlight.
He doesn't say, but use a hole saw to cut the access hole under the headlight.
http://rigs.corequipment.com/cebby_W...ling.htm#relay

[hulkmn069]

Originally Posted by Bob D.

Here is a how to on changing the module via the headlight.
He doesn't say, but use a hole saw to cut the access hole under the headlight.
http://rigs.corequipment.com/cebby_W...ling.htm#relay

easy on the hole saw guys the front bumper will slide out if you un do the bolts on both sides and then coax the top of it. just make sure you take out all the grille bolts and or screws too. if you loosen all the things that are connected you'll be able to get your hand in there to get the relay out

[pdltfc]

Originally Posted by Bob D.

Here is a how to on changing the module via the headlight.
He doesn't say, but use a hole saw to cut the access hole under the headlight.
http://rigs.corequipment.com/cebby_W...ling.htm#relay

Isn't it possible to check the fan by disconnecting it and connect it directly
to the positive and negitive of the battery??

The description of gaining access to the relay and fan removal was super.
The problem is I haven't been able to manuver the shroud assembly out.
I have removed the 4 bolts holding the blade but still have been unsuccesful in removing it. Can the shroud be easily be broken?

I have also loaned a fan clutch removal tool from different auto supply stores
but the wrenches supplied will fit the large nut but I haven't found anything to stop the water pump pulley from turning.

[Bob D.]

Originally Posted by pdltfc

Isn't it possible to check the fan by disconnecting it and connect it directlyto the positive and negitive of the battery??

Yes, you can diagnose the relay by running 12v to the fan.

The problem is I haven't been able to manuaver the shroud assembly out.
I have removed the 4 bolts holding the blade but still have been unsuccesful in removing it. Can the shroud be easily be broken?

I have also loaned a fan clutch removal tool from different auto supply stores
but the wrenches supplied will fit the large nut on fan clutch but I haven't found anything to stop the water pump pulley from turning.

What year and engine/fan set up are we talking about here? It makes a difference.
You may need a special Chrysler tool - 6958 Spanner Wrench and 8346 adapters to remove the mechanical fan/clutch unit.
Threads on viscous fan drive are RIGHT HAND.

Remove the fan shroud-to-upper crossmember nuts.
Remove the fan shroud and fan blade/viscous fan drive assembly as a complete unit from vehicle.

If your Jeep is a 4 liter, 1999-2004 with electric fan only, remove the fan and housing up and to the rear.
If it's a 4 liter, 1999-2004 with a auxiliary mechanical fan, it's easier to leave the mechanical fan in place and remove the electric fan through the front by loosening the radiator and grill.

[pdltfc]

Thanks Bob D for your reply.

[Dean Cottier]

I'm having the same problem with an (01) 4.0 overheating installed a new fan motor already looking for the relay fuses are good changed temp sensor too

[83T/A98Blazer]

Just replaced the relay on my sis-in-law's 99 Grand Cherokee. The info here was really great, I never would've known to look for that relay there. The bumper removal was really easy. Seven screws on the grille and one bolt on the corner of the bumper cover. I could NOT get the headlight assy to come off. I looked closely at the pics in the post above, it looks like the headlight assembly might've broken where it was supposed to come out of the socket on the right hand side. Anyway, I thought I'd give a vote to pulling the bumper cover, or just the one side and the grille, it was pretty easy.