LOST JEEPS
http://www.lostjeeps.com/forum/phpBB3/

AC Issues and Electric Fan Operation
http://www.lostjeeps.com/forum/phpBB3/viewtopic.php?f=5&t=86492		 Page 1 of 1
Author:  KyleDriver [ Tue Apr 25, 2017 11:01 pm ]
Post subject:  AC Issues and Electric Fan Operation
Yes, I read the Noob Guide!

Hello everyone, I purchased a CRD recently and I am looking for some information. So far I have been sifting through threads trying to find what I need, but I can spend days looking through them.

Question 1: What is normal electric fan operation? Should it come on immediately when the AC is turned on and stay on? Or does it only come on intermittently?

Question 2: AC clutch does not engage at all. I will be checking things out tomorrow and inspecting the relays and grounds. Is freon level something I can easily check or is that something I will have to bring it into the shop for?

Question 3: Where can I find a wiring diagram of the AC system?

I appreciate any help I can get. Thank you
Author:  flash7210 [ Wed Apr 26, 2017 12:33 am ]
Post subject:  Re: AC Issues and Electric Fan Operation
The electric fan will come on when one of the AC pressure switches tells it to or when coolant temp gets above 205F.
You can test the fan by pulling any one of the fan relays. It should come on at low speed.

You can get a set of AC pressure gauges from the auto parts store but its best to let a shop do it.
There is a relay that activates the clutch. You could try swapping relays to see if it has any effect.

Given your symptoms, I suspect low freon. I would start there.
Author:  Billybob [ Wed Apr 26, 2017 9:14 am ]
Post subject:  Re: AC Issues and Electric Fan Operation
KyleDriver wrote:
Yes, I read the Noob Guide!

Hello everyone, I purchased a CRD recently and I am looking for some information. So far I have been sifting through threads trying to find what I need, but I can spend days looking through them.

Question 1: What is normal electric fan operation? Should it come on immediately when the AC is turned on and stay on? Or does it only come on intermittently?

Question 2: AC clutch does not engage at all. I will be checking things out tomorrow and inspecting the relays and grounds. Is freon level something I can easily check or is that something I will have to bring it into the shop for?

Question 3: Where can I find a wiring diagram of the AC system?

I appreciate any help I can get. Thank you


What year is your Jeep?

As stated, have a shop check the refrigerant level....there is a switch that checks for low level of refrigerant that will stop the AC clutch relay from energizing if this is low.

Swap over the AC relay...inside the fuse/relay box under the hood...with an identical one nearby.

Your ground to the AC clutch may be bad....ground the AC housing to a clean engine point temporarly to see if that helps.

You can pull out the AC relay and with engine running briefly jumper the female plugs 30 and 87 together inside the relay...the clutch should operate if there is a good ground. I say briefly because you will damage the compressor by running it for a period of time if the refrigerant is low!

You can download manuals here for your year...except 2004.... use 2003 if needed....includes Wiring Diagrams and Theory of Operations. :wink:

http://www.colorado4wheel.com/manuals/Jeep/KJ
Author:  KyleDriver [ Wed Apr 26, 2017 1:05 pm ]
Post subject:  Re: AC Issues and Electric Fan Operation
Billybob wrote:
KyleDriver wrote:
Yes, I read the Noob Guide!

Hello everyone, I purchased a CRD recently and I am looking for some information. So far I have been sifting through threads trying to find what I need, but I can spend days looking through them.

Question 1: What is normal electric fan operation? Should it come on immediately when the AC is turned on and stay on? Or does it only come on intermittently?

Question 2: AC clutch does not engage at all. I will be checking things out tomorrow and inspecting the relays and grounds. Is freon level something I can easily check or is that something I will have to bring it into the shop for?

Question 3: Where can I find a wiring diagram of the AC system?

I appreciate any help I can get. Thank you


What year is your Jeep?

As stated, have a shop check the refrigerant level....there is a switch that checks for low level of refrigerant that will stop the AC clutch relay from energizing if this is low.

Swap over the AC relay...inside the fuse/relay box under the hood...with an identical one nearby.

Your ground to the AC clutch may be bad....ground the AC housing to a clean engine point temporarly to see if that helps.

You can pull out the AC relay and with engine running briefly jumper the female plugs 30 and 87 together inside the relay...the clutch should operate if there is a good ground. I say briefly because you will damage the compressor by running it for a period of time if the refrigerant is low!

You can download manuals here for your year...except 2004.... use 2003 if needed....includes Wiring Diagrams and Theory of Operations. :wink:

http://www.colorado4wheel.com/manuals/Jeep/KJ


It's a 2006. So first thing I should do is have the refridgerant level checked? I'll do some of the trouble shooting with the grounds and relays before I bring it in.

Can I pull the relay for the electric fan and shirt that to make sure that's working?
Author:  KyleDriver [ Wed Apr 26, 2017 6:09 pm ]
Post subject:  Re: AC Issues and Electric Fan Operation
Well I found the issue. The low pressure switch was disconnected by the previous owner. I called him up and asked him about it and he told me he didn't want the compressor running in the winter while the defrosters are on. So I plugged it in and it blows cold air but it makes a nasty screeching/squeaking noise from the compressor.

Before I found the disconnected switch, I jumped the compressor for a few seconds to make sure it works. Could I have damaged the compressor doing that? Or does the compressor need to be ran because it hasn't for several months? I turned the AC on and off about 20 times idling and the noise didn't get better. It seems to be worse at 1 and 2 dash fan speeds.
Author:  GordnadoCRD [ Wed Apr 26, 2017 7:54 pm ]
Post subject:  Re: AC Issues and Electric Fan Operation
one of the reasons they program ac systems to run with defrost in the winter is the system has to be circulated to keep the lubrication oil mixed with the Freon.

I seriously doubt that jumping the clutch would have caused any damage.

Before running it much I recommend taking it to a shop that can do proper AC servicing, they will remove all the freon from the system, and put it under vacuum for several minutes. This causes all the moisture that may be in there to boil away. then they recharge it with the proper amount of refrigerant and oil. This way you know running it won't be damaging anything.
Page 1 of 1 All times are UTC - 5 hours [ DST ]
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
http://www.phpbb.com/