A/C - AZC Module, Innacurate Temperature Settings

NUMBER: 24-16-99

GROUP: Heating & A/C

DATE: Aug. 20, 1999

SUBJECT:
Automatic Zone Control (AZC) Module Re-Calibration

OVERVIEW:
This bulletin involves re-calibrating the AZC Module for more accurate interior temperature settings.

MODELS:
1999 (WJ) Grand Cherokee

SYMPTOM/CONDITION:
Some customers may experience dissatisfaction with the temperature setting in the AZC control module. Customers may feel that they have to go beyond what they feel are normal settings to be comfortable. Some examples of typical customer complaints are as follows:

- Having to set the temperature too high or low to maintain a comfortable passenger compartment

- Constantly having to adjust the temperature setting when in automatic mode

- Temperature fluctuation in the automatic mode Temperature overshoot in automatic mode

DIAGNOSIS:
If customers indicate that their vehicle exhibits these conditions, perform the Repair Procedure.

EQUIPMENT REQUIRED:

DRB III(R) containing minimum software release 30.2
CH7OOO Cable

REPAIR PROCEDURE:
THIS REPAIR IS COMPATIBLE WITH DAIMLERCHRYSLER'S MOBILE SERVICE PROGRAM AND DOES NOT REQUIRE HOISTS OR OTHER FULL SERVICE FACILITY SPECIAL EQUIPMENT.

1. Connect the DRB III(R)to the J1962 connector

2. From the Standalone Main Menu choose # 11998 to 2000 Diagnostics

3. From the Select System menu choose # 3 Body

4. From the Select Body System menu choose # 4 Automatic Temp Control

5. Under the Automatic Temp Control choose # 9 Miscellaneous

6. Under the Select Miscellaneous Function menu choose # 4 Re-program AZC Head

7. Text will appear which will read:
"This procedure will re-program the AZC head - Do you wish to continue" - Push Yes

8. At this point the DRB III(R) will begin to reprogram the AZO head. This part of the procedure could take up to several minutes. At no time should the DRB III(R) be disconnected from the vehicle during the procedure.

9. Once the DRB III(R) is finished the DRB III(R) will inform the user about the status of the test.

10. If the re-programming failed, this procedure will need to be repeated as prompted by the DRB III(R).

11. If the re-programming has been completed successfully, the DRB III(R) will prompt the user to pull the IOD (Fuse # 15) from the under hood PDC for 10 seconds.

12. After the IOD fuse has been put back in the ignition must be left in the "On" position for at least 45 seconds.

13. After 45 seconds, the procedure is complete and it is safe to disconnect the DRB III(R).

POLICY: Reimbursable within the provisions of the warranty.

TIME ALLOWANCE:

Labor Operation No: 24-75-01-92 0.3 Hrs.

FAILURE CODE: 15 - Calibration