99 Grand Cherokee Ltd Heat on passenger side cold on Drivers side. WHATS WRONG??

nosguy · 12-29-2007, 10:57 AM

Hello everyone, I am new to the forum and am having heater problems with my 1999 Grand Cherokee ltd. I am getting heat out of the passenger side but cold air out of the drivers side. This just started this morning. I have started to do some research on the forum and it sounds like blend doors?? I have also read to hold the AC and Re-circ buttons down and turn the temp knob one click to get a fault code. I did this and two codes came up. It flashes between 54/56. Anyone have any suggestions as to what could be the problem?
Also what do I need to purchase to fix it and where can I purchase it?
Last question, do I need to pull out the dash board?

Thank you in advance
Great forum!!

CMARJEEP · 12-29-2007, 11:51 AM

yes yes and yes. expensive to have done and time consuming to do yourself. if you take it in its going to be in the $1000 range. if you do it yourself it will be in the 5-10 hour range. look at the heater treater on ebay though. it takes an hour to put in but you will lose your dual climate.

GibsJeep · 12-29-2007, 01:08 PM

That sucks you have that problem on the driver side. My passenger side does that, so when Im drivin I dont have to deal with it, only the person sitting shotgun.

nosguy · 12-29-2007, 07:45 PM

UPDATE : I took out the glove box to see whats going on. I pulled the actuator motor off and noticed the plastic pin that stops the shaft was broken off. I can spin the shaft by hand multiple times in either direction. Also, with the actuator motor plugged in, I was told the motor should rotate when you go from the high to low temp. setting. I tried this and nothing happend.

Can anyone confirm my problem?
If it is the blend doors, can I I just get a used re-circ box and actuator motor from my local auto wrecking yard? I know I would have to drain the coolant and AC and remove the dash, but would doing this take care of my problem?
Last question, how do I clear the fault codes?

thanks again guys!!

jeepster2000 · 12-30-2007, 01:06 AM

Quote:

Originally Posted by nosguy

Last question, how do I clear the fault codes?

thanks again guys!!

my blend doors have been done by the dealer as it's under warrenty (just bought it luckily enough) BUT the error codes are still there even though the heater/climate is now working fine,so i am interested in how you clear the codes as well?
thought the dealer would of done that !!!!

JG_Canuck · 12-30-2007, 08:19 AM

www.wjjeeps.com is your ultimate resource:

"To clear the codes hold either the A/C or the recirc button down for 3 seconds when the AZC is in diagnostic mode."

If you are going to remove the dash, get the (new) parts from the dealer. You don't want to wind up replacing j/y ones as well.

Some people have used the Heater Treater (search ebay). No dash removal, but you lose dual zone function.

cmonson · 12-30-2007, 08:42 AM

Just buy the heater treater on evilbay. You most deffinately have a blend door failure. The dual climate is a waste of space anyway. The heater treater takes out the Dual blend doors, and gives you one door (thus no dual controls).

As for the motor, I am not sure. Maybe the motor will not work as you have a code, and by default it will not allow to turn.

nosguy · 12-30-2007, 08:43 AM

UPDATE:

I cut out a hole in the re-circ box this morning. Found the far side (near firewall, passenger side vent) blend door to be working great. The near side (drivers) was broken at the shaft. I think I can replace the driver side with a new blend door from the dealer. What do you guys think? I was able to remove the drivers side blend door and just tape the upper hole shut to give me some heat for now.
Also the actuator motor does not spin when plugged in and I adjust the temp knob from high to low. Is it not working because of the fault code? Do I need to clear the code to make it work again?
I still don't quite understand how to clear the codes. Can someone please tell me step by step how to do it.
Thank you

cmonson · 12-30-2007, 09:14 AM

can you see if there is power going to the motor on the drivers side? Also, can you take a pic of the hole you cut?

cmonson · 12-30-2007, 09:15 AM

I meant to post this as well to re-set...

Calibrate the door actuators after making any repairs to the AZC system. To calibrate the door actuators proceed as follows:

1. Turn the ignition on.
2. Set the AZC to automatic.
3. Turn the ignition off.
4. Remove the IOD fuse from the Power Distribution Center. Wait several seconds, and then install the IOD fuse.
5. Turn the ignition on. Do not touch any of the AZC controls for at least one minute to allow the calibration function to run to completion.