[BillShort]

If air conditioner is on should the cooling fan be on - If so what turns it on because mine only comes on when engine temps turns it on.

1999 Grand Cherokee Limited 4.7

[the88thpianoman]

As far as I know, our cooling fans are tied only to engine temp and do not stay on with ac.

[JForest2]

Not sure what year WJ you have but on my 03 I6, whenever I put the ac on the fan went on also...


James

[the88thpianoman]

Interesting... my 03 I6 does not...

[BillShort]

I have a 99 Grand Cherokee Limited 4.7. Sounds like one of you guys may have a problem.

[Bubba3200]

I will have to check mine....02 Overland. But the theory here should be that the fan comes on when the a/c is selected. Why?? Because the condensor has to have air across it at all times to cool the freon. Just like your home unit....when it is on the outside condensor fan should be running. If the fan is not running at stop or slow speed the a/c will not work right and a over heat condition could occur.

The hydraulic fan on mine seems to have variable speeds and it seems to adjust accordingly.

[ultimo]

I have both hydraulic and electrical fan, and sometimes the electrical fan does not turn on unless idling for a long time. So i guess thats ok. AS the hydraulic fan blows all the time anyways.

[WiCkeDuDe]

Originally Posted by ultimo

I have both hydraulic and electrical fan, and sometimes the electrical fan does not turn on unless idling for a long time. So i guess thats ok. AS the hydraulic fan blows all the time anyways.

They didnt put the hydraulic fans on the 4.0s.

[patrick983]

on the 4.7's the electric fan should be on with the a/c

[BillShort]

Ok Cool the fan should be on with AC. Mine is not coming on, what controls the fan. The fans does come on from from engine temp.

[ultimo]

Originally Posted by WiCkeDuDe

They didnt put the hydraulic fans on the 4.0s.

I added it in Bought the mopar part and clutch from Kolak. I believe those with the tow package came with it too

[BillShort]

Come on - Somebody must have the answer.

[cedxc2005]

Originally Posted by Bubba3200

I will have to check mine....02 Overland. But the theory here should be that the fan comes on when the a/c is selected. Why?? Because the condensor has to have air across it at all times to cool the freon. Just like your home unit....when it is on the outside condensor fan should be running. If the fan is not running at stop or slow speed the a/c will not work right and a over heat condition could occur.

The hydraulic fan on mine seems to have variable speeds and it seems to adjust accordingly.

THIS. It is exactly as Bubba said. I have an 04 WJ I6. AC on = electric fan on (no hydraulic fan). Why? Because your AC needs air over the condenser to make cold air. Totally normal. Note that if your Jeep hasn't warmed up all the way, if you turn off the AC, the fan will go off. Theoretically, if you are moving, it should turn off as well, but I don't know if that is the case, and it's kinda hard to check...

Long story short, electric fan operation with AC on is normal. No worries.

[BillShort]

Ok guys i know the fan should be on when the ac is turned on. But mine does not, and causes a high pressure problem. The fan comes on when engine temp is over 215, so i know the fan works.

So what am i missing - what turns the the fan on when i press the ac button?

[compcrasher86]

Originally Posted by ultimo

I added it in Bought the mopar part and clutch from Kolak. I believe those with the tow package came with it too

OH You're talking about the hydraulic clutch fan. Yeah, the one you tie to the waterpump pully. That comes standard on tow package 4.0s. The other guy was thinking about the main hydraulically operated fan that works off of the power steering pump that is on the 4.7 WJs instead of the electric one we have on the 4.0s