Go Back   Jeep Garage - Jeep Forum > Jeep Platform Discussion > Grand Cherokee - WJ > Troubleshooting/Problems

Join Jeep Garage Today
Reply
 
Thread Tools Display Modes
 
  #1  
Old 09-05-2011, 03:49 PM
Member
My Jeep: 2001 4.7L WJ
 
Join Date: Sep 2011
Posts: 8
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1124
edfred is on a distinguished road
strange working ac/heater WJ limited 2001

My ac/heater isn't working like it should.
At first when it's on automatic it works ok but after a while there is no air coming out of the vents.
When i turn it to manual and set the ventilator on high i can hear the ventilator is working but still no air coming out off the vents.
Also the ventilator unit is condensing very heavy so my girlfriend is getting her feet's wet.

Anybody any idea?
__________________

__________________
Reply With Quote
  #2  
Old 09-05-2011, 05:46 PM
2005JGC's Avatar
Senior Member


My Jeep: 2005 4.7L WK
 
Join Date: Nov 2010
Location: Portland, OR
Posts: 2,751
Thanks: 51
Thanked 69 Times in 58 Posts
Rep Power: 1652975
2005JGC has a reputation beyond repute2005JGC has a reputation beyond repute2005JGC has a reputation beyond repute2005JGC has a reputation beyond repute2005JGC has a reputation beyond repute2005JGC has a reputation beyond repute2005JGC has a reputation beyond repute2005JGC has a reputation beyond repute2005JGC has a reputation beyond repute2005JGC has a reputation beyond repute2005JGC has a reputation beyond repute
Re: strange working ac/heater WJ limited 2001

I wonder if your evaperator is freezing up solid. Will it continue to blow without the A/C on (just the fan)?
__________________

__________________
2005 Jeep Grand Cherokee - Gone but not forgotten!

Reply With Quote
  #3  
Old 09-05-2011, 06:08 PM
Frango100's Avatar
Premium Member

My Jeep: 2004 4.7L WJ
 
Join Date: Dec 2009
Location: Brazil
Posts: 4,925
Thanks: 9
Thanked 93 Times in 88 Posts
Rep Power: 525880
Frango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond repute
Re: strange working ac/heater WJ limited 2001

First of all it seems that the water drain from the HVAC housing is plugged, causing the waterdrips on the passenger side. This drain comes out in the engine bay, so try to open it with some kind of wire.
When the airflow stops again, try to put it in full heat and see if after a while its starts blowing again. If yes, it was probably ice closing the evaporator.
__________________
Frank

JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
KYB Gas-a-Just shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.

VW Beetle 2.0 TSI 2013
My new toy
Reply With Quote
  #4  
Old 09-06-2011, 11:10 AM
Member
My Jeep: 2001 4.7L WJ
 
Join Date: Sep 2011
Posts: 8
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1124
edfred is on a distinguished road
Re: strange working ac/heater WJ limited 2001

Thanks for the reactions so far.

@2005GJC the fan continues to blow when i turn off the ac and after a while air will come out off the vents again.

@frango i don't think the drain is plugged because i discovered that the housing is becoming complete wet on the outside and even ice will form on it.

The problem wasn't a onetimer and happens each time i drive the car.


Icing up off the evaporator seems to be logical.
How is this possible?
__________________
Reply With Quote
  #5  
Old 09-07-2011, 12:45 PM
Frango100's Avatar
Premium Member

My Jeep: 2004 4.7L WJ
 
Join Date: Dec 2009
Location: Brazil
Posts: 4,925
Thanks: 9
Thanked 93 Times in 88 Posts
Rep Power: 525880
Frango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond repute
Re: strange working ac/heater WJ limited 2001

There is a temperature sensor on the evaporator which must take care that freezing of the moisture on the evaporator doesn't occur. It should switch the A/C compressor clutch off when a temperature of 1.1 C is reached and prevents in this way the freezing of the evaporator. Maybe this sensor is bad or the contacts of the connector corroded.
The bad thing is that you have to remove the whole HVAC housing (read complete dash) to get access to this sensor. There is maybe a way to measure it first before deciding to change it.
The 2 wires from this sensor are going to the Body Control Module, connector C2 points 16 (sensor signal) and point 20 (sensor ground). I have however no values for this sensor to know if its ok or not.
__________________
Frank

JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
KYB Gas-a-Just shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.

VW Beetle 2.0 TSI 2013
My new toy
Reply With Quote
  #6  
Old 09-09-2011, 11:16 AM
Member
My Jeep: 2001 4.7L WJ
 
Join Date: Sep 2011
Posts: 8
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1124
edfred is on a distinguished road
Re: strange working ac/heater WJ limited 2001

of course the switch is at a place that's hard to reach but anyway i'm gonna change it.
Went to the dealer and ordered a switch unfortunally they couldn't tell me what the best way to do it.
The new jeep dealer is a former lancia dealer this because off the merge with fiat.
They took an hour to program my rke wich is normally a 5 minute job.

Because i'm gonne take out the dash i will change the blenddoors at the same time.

If the fix worked i will let you know
__________________
Reply With Quote
  #7  
Old 09-09-2011, 03:57 PM
Frango100's Avatar
Premium Member

My Jeep: 2004 4.7L WJ
 
Join Date: Dec 2009
Location: Brazil
Posts: 4,925
Thanks: 9
Thanked 93 Times in 88 Posts
Rep Power: 525880
Frango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond repute
Re: strange working ac/heater WJ limited 2001

Jeep manual tells to open up the HVAC housing to get access to the evaporator. The temperature sensor is placed in the evaporator core. For some reason (and they donīt tell why) the new sensor has to go in a different hole in the evaporator core then the old one was installed into.
__________________
Frank

JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
KYB Gas-a-Just shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.

VW Beetle 2.0 TSI 2013
My new toy
Reply With Quote
  #8  
Old 09-10-2011, 12:16 PM
Member
My Jeep: 2001 4.7L WJ
 
Join Date: Sep 2011
Posts: 8
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1124
edfred is on a distinguished road
Re: strange working ac/heater WJ limited 2001

This sounds new to me.
I read the instruction in the manual on nagca.com and this doesn't mention another position.
I'm going to look into this before removing everything.
__________________
Reply With Quote
  #9  
Old 09-10-2011, 05:43 PM
Frango100's Avatar
Premium Member

My Jeep: 2004 4.7L WJ
 
Join Date: Dec 2009
Location: Brazil
Posts: 4,925
Thanks: 9
Thanked 93 Times in 88 Posts
Rep Power: 525880
Frango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond repute
Re: strange working ac/heater WJ limited 2001

Here follows the page from the Jeep manual.
Attached Images
File Type: jpg 11092011776.jpg (163.9 KB, 6 views)
__________________
Frank

JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
KYB Gas-a-Just shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.

VW Beetle 2.0 TSI 2013
My new toy
Reply With Quote
  #10  
Old 09-11-2011, 10:47 AM
Member
My Jeep: 2001 4.7L WJ
 
Join Date: Sep 2011
Posts: 8
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1124
edfred is on a distinguished road
Re: strange working ac/heater WJ limited 2001

i looked into the manual i have and this page isn't in it.
Is this the manual for a 2001 WJ?
My manual mentions a low pressure switch on the accumulator but in the whole section of the ac (chapter 24) a switch like you mention isn't spoken off.
Strange isn't it?

I'm gonna check the switch on the accumulator first.
__________________
Reply With Quote
  #11  
Old 09-11-2011, 02:38 PM
Frango100's Avatar
Premium Member

My Jeep: 2004 4.7L WJ
 
Join Date: Dec 2009
Location: Brazil
Posts: 4,925
Thanks: 9
Thanked 93 Times in 88 Posts
Rep Power: 525880
Frango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond repute
Re: strange working ac/heater WJ limited 2001

My manual is for the 2004 WJ, didn't know that the airco system was different on older WJ's. Don't know then how evaporator freezing is prevented, when there is no sensor to sense it. On my WJ there is a pressure transducer in the line close to the condensor, but i don't have a low pressure switch, nor accumulator.
__________________
Frank

JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
KYB Gas-a-Just shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.

VW Beetle 2.0 TSI 2013
My new toy
Reply With Quote
  #12  
Old 09-12-2011, 12:57 AM
Frango100's Avatar
Premium Member

My Jeep: 2004 4.7L WJ
 
Join Date: Dec 2009
Location: Brazil
Posts: 4,925
Thanks: 9
Thanked 93 Times in 88 Posts
Rep Power: 525880
Frango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond repute
Re: strange working ac/heater WJ limited 2001

I did download the manual from the nagca site and eventhough the manual is for 2001/2004 models, there are some differences in the airco system.
If your jeep has the accumulator (which is called filter dryer on mine), then it has a low pressure switch on this accumulator and a high pressure switch close to the condensor. Both switches are in series and connected to the PCM and can switch the compressor on and off. This low pressure switch has the function to prevent icing of the evaporator in this system. It is probably faulty on your jeep.
__________________

__________________
Frank

JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
KYB Gas-a-Just shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.

VW Beetle 2.0 TSI 2013
My new toy
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
2001 WJ Limited 10-Disc CD Changer Help Amelie Audio/Visual/Navigation 18 12-20-2011 10:27 PM
A/C and Heater Controls Not Working? bommar37 Troubleshooting/Problems 8 07-24-2011 03:17 PM
2002 GC heater blower not working grumpyden Troubleshooting/Problems 6 07-13-2010 01:59 PM

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 02:41 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Copyright 2012 - JeepGarage.Org
The Jeep Grand Cherokee Owners Community