auxilary/electric fan problems 4.0
Repo_agent
03-28-2006, 08:24 PM
2001 Cherokee with 4.0L. It has a belt driven fan and a secondary electric fan.
Does this electric fan only come on with AC on? Someone has unplugged the fan and hooked it up to the AC clutch power and a ground so the fan now by passes the relay and whatever else and switches on when the AC cycles the clutch. I hooked the fan up right and now I cant get it to work.
The fan motor is good. The relay and fuse is good.
Does fan come on with AC as soon as you turn AC on? And does fan come on with AC off if coolant temp reaches a certain degree?
Anyone now why this fan is not being switched on?
There was a code that came up for the fan after I hooked it up right. It was a Aux fan Ckt problem code (open or short)
I know you Jeep guys know your Jeeps so I am hoping for some good input. I had a 98 Cherokee that I wish I would have never sold. I just got my parents to buy a 2001. And truthfully I am a Chevy guy.
Also when AC is on should the AC compressor clutch run in short cycles or should it stay on continously? Or does it depend on outside temp?
Does this electric fan only come on with AC on? Someone has unplugged the fan and hooked it up to the AC clutch power and a ground so the fan now by passes the relay and whatever else and switches on when the AC cycles the clutch. I hooked the fan up right and now I cant get it to work.
The fan motor is good. The relay and fuse is good.
Does fan come on with AC as soon as you turn AC on? And does fan come on with AC off if coolant temp reaches a certain degree?
Anyone now why this fan is not being switched on?
There was a code that came up for the fan after I hooked it up right. It was a Aux fan Ckt problem code (open or short)
I know you Jeep guys know your Jeeps so I am hoping for some good input. I had a 98 Cherokee that I wish I would have never sold. I just got my parents to buy a 2001. And truthfully I am a Chevy guy.
Also when AC is on should the AC compressor clutch run in short cycles or should it stay on continously? Or does it depend on outside temp?
Ray H
03-29-2006, 05:39 AM
The electric fan is supposed to cycle on and off with the A/C compressor. Its also supposed to come on if the coolant temp reaches around 220. Since the A/C compressor cycles when the defrost is on, so will the fan.
It sounds like it was working as it should to begin with.
It sounds like it was working as it should to begin with.
Repo_agent
03-29-2006, 09:48 AM
It was only working because someone UNPLUGGED the fan and attatched one fan wire straight to chassis ground and one fan wire to AC clutch hot wire.
I hooked it up the right way and now it wont work.
So the previous owner could not find the problem so he hooked it up that way. Its obviously the wrong way.
I hooked it up the right way and now it wont work.
So the previous owner could not find the problem so he hooked it up that way. Its obviously the wrong way.
AlohaBra
03-29-2006, 10:17 AM
According the sevice manual, the fan is controlled through the Powertrain Control Module.
Your fix will work if it is fused properly. Although that fan should not be needed at road speeds (which is why it is on the powertrain CM).
That fan was added when Jeep "shortened" the 4 liter engine so it will fit into the XJ body (1987) by using a shorter water pump and two fans.
Your fix will work if it is fused properly. Although that fan should not be needed at road speeds (which is why it is on the powertrain CM).
That fan was added when Jeep "shortened" the 4 liter engine so it will fit into the XJ body (1987) by using a shorter water pump and two fans.
Repo_agent
03-29-2006, 07:15 PM
That wasnt my fix it was someone elses.
And that way will only work with the AC compressor on.
I hooked it up right and want it to come on with AC or by temp switch.
And that way will only work with the AC compressor on.
I hooked it up right and want it to come on with AC or by temp switch.
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