John Boy

I have a 2002 Grand Cherokee with 8 cyl engine. I turned on the a/c yesterday and could hear the fan running, but nothing was coming out of the vents. When I changed the distribution (dash, defroster etc.), I could hear a motor running, but no change in the output. Tried it on heat and got nothing either. Tried the recirc and didn't hear the door and no change.

Any ideas on what the problem is? Is any part of the distribution system hooked up to vacuum? Or is it all electrical?

Thanks

ol"blue

Maybe this will help in some way.>>->http://www.wjjeeps.com/hvac_sub_assembly.htm
And Welcome to CF.

John Boy

Thanks. I looked at the link and it may solve an older problem I had, which was limited/no heat on passenger side. Of course that's the one that you have to take apart the entire dash.

The thing is now I'm not getting any air out of the vents on either side or the defrosters and no code is showing. Looks like this may be a different situation based on the limited description they provided. What do you think?

Thanks again

ol"blue

Did you remember to re-hook the vacuum line that actuates the blend doors? http://www.wjjeeps.com/hvac/instrume...removal_13.jpg

This has some nice diagrams too.http://www.wjjeeps.com/hvac_sub_install.htm

John Boy

Do the AZC systems have a vacuum line that actuates the blend door? My brother and I suspected a vacuum problem, but weren't sure if the AZC system used vacuum or was electrically controlled.

ol"blue

It looks like it is electrically controlled.
This has a write up that tells how to calibrate the ATZ door actuators. http://www.wjjeeps.com/climate.htm

John Boy

I checked the system fault codes and found out that I had a "52" and a "56". According to the fault description and write-ups, it means the shaft on the recirc motor and the right actuator stripped a giblet.

52 = AI (Recirc) door travel range too large
56 = Right temperature door travel too large

So would these two faults be enough to make it so NO air comes out of any of the vents? Blows like crazy when the fan is turned up, but nothing comes out. Or do you think there is something else in addition to these faults?

Thanks

ol"blue

No, I think that would do it. The blend doors aren't able to properly direct the flow of air to the selected positions because they are loose (turning) on the shafts.IMO
The following link will give you some ideas on repairs.>>->http://www.wjjeeps.com/hvac_sub_assembly.htm

John Boy

My brother's got my whole dash apart and is well on the way to completing the repairs. He said the recirc door had broken off and was laying on the intake side of the fan. The higher the fan setting, the harder it pulled the door down on top of the intake. No wonder I wasn't getting anything at all out of any of the vents. Turns out the heater core was leaking too. So, he's replacing it while he had it apart. He said he didn't want to have to take it apart again.

Hey Ol' Blue....Thanks for all of the links you posted. Made the job a whole lot easier than trying to figure it out as he went.

Stewhatch

Ol Blue - aka YODA