I found a calibration procedure for the AZC. Could this be the issue if the door is moving but still giving a code 52?
I still get a 52 but my door still works ok. I am told the stops are worn which allows the rotation beyond limits and in time the plastic will become over stressed and break. I decided to simply wait and after a year, it is still working.
I know this is an old post, but hopefully someone can answer... We are very close to purchasing a 2003 Grand Cherokee(Euro version), but the aircon makes a 'knocking' noise(Sounds like plastic inside) when first turned on. It goes for a few seconds, stops, then a few more times then stops and is fine. Previous owner says its done it for 3yrs that he has owned it. The aircon and what not all works perfectly though. Is this the blend door on it way out? Or something worse?
No......no air on pass side sounds like blend door problem. This is caused by plastic door shaft breaking. There is a easy MOPAR fix that one can do. One needs for tools a plunge saw (Sonicrafter) or heat knife to cut the plastic housing neatly for access and about 10 ft of copper wire to run from the battery to the work area to rotate the door actuator to the 2:00 position for easy insertion of the new blend doors. The kit comes with a template for cutting and I found that using a white magic marker allowed me to trace a visible line for cutting. Accurate cutting is necessary so that one does not puncture the evaporator coil which is near the access that one makes. The repair cost about $100 which is much cheaper than the $800 that the dealer wanted and the new blend doors had metal shafts. After repair the system needs to be calibrated using the AZC procedure.
Blower motor is a squirrel cage under glove box held in place with 3 brass torx screws. Once screws removed, blower will drop down. It may be easier to reach one of the torx screws by removing the right foot pannel which is held in place with one screw. A nut driver is easier to use than a torx bit as the screws will fall out when loose. No need to disconnect electrical unless replacing blower.