Jeep Tech Tip: Poor A/C Performance – UnderhoodService

Jeep Tech Tip: Poor A/C Performance

Some Jeep Liberty and Nitro owners may complain that A/C performance is poor and that the A/C is not cooling enough or fails to keep the passenger compartment cool. This update will provide customers with improved A/C performance.

Models
2007-‘08 (KA) Nitro
2008 (KK) Liberty

Jeep AC performanceSome customers may complain that A/C performance is poor and that the A/C is not cooling enough or fails to keep the passenger compartment cool. This update will provide customers with improved A/C performance.

Diagnosis
1. Is the vehicle a 2007 model year vehicle?
Yes — Replace the temperature control module with PN 55111884AF. Follow the procedures in TechCONNECT. Door calibration will be performed automatically once the new control module detects key on.
No — Proceed to Step No. 2.

2. Is the vehicle build date before May 30, 2008?
Yes — Perform the flash repair Procedure and A/C system recovery and recharge.
No — For vehicles built between May 30, 2008, and before July 2, 2008, perform Step 7 of the Repair Procedure.

Repair Procedure

When performing this repair procedure, the software release level in the StarSCAN or equivalent must be programmed with 9.03 level software or higher.

NOTE: If this flash process is interrupted/aborted, the flash should be restarted.

1. Install a battery charger and verify that the charging rate provides approximately 13.5 volts. Set the battery charger to continuous charge. Do not allow the charger to time out during the flash process. Remove the charger from the battery when the flash process is complete.
2. Connect and power on the StarSCAN.
3. Turn the ignition switch on.
4. Retrieve the old HVAC part number. Using the StarSCAN or equivalent tool at the “Home” screen:

a. Select “ECU View”
b. Touch the screen to highlight the HVAC in the list of modules.
c. Select “More Options”
d. Select “ECU Flash”
e. Record the part number at the top of the “Flash HVAC” screen for later reference.
f. Select “Browse for New File.” Follow the on screen instructions.
g. Select “Download to Scan tool.”
h. Select “Close” after the download is complete, then select “Back.”
i. Highlight the listed calibration.
j. Select “Update Controller.” Follow on screen instructions.
k. When the update is complete, select “OK.”
l. Verify the part number at the top of the “Flash HVAC” screen has updated to the new part number.

5. Perform an A/C system recovery and recharge following the procedures outlined in DealerCONNECT. A/C systems on these vehicles were originally charged with 20 oz. of refrigerant. By performing a system recovery and recharge with 18 oz. of refrigerant, improved A/C performance can be achieved.

Courtesy of ALLDATA.

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