Grand Cherokee 2WD V8-5.7L VIN 2 (2005)
Control Module HVAC: All Technical Service Bulletins
A/C - Settings Drift/Slow to Adjust/Increment Too Small
NUMBER: 24-010-05 REV. A
GROUP: Heating & Air Conditioning
DATE: November 24, 2005
THE StarSCAN(R) FLASH FILES FOR THIS BULLETIN ARE AVAILABLE VIA THE INTERNET.
THE FLASH FILE WILL BE AVAILABLE ON THE NEXT StarSCAN(R) UPDATE CD RECEIVED AFTER CD 6.04.
THIS BULLETIN SUPERSEDES TECHNICAL SERVICE BULLETIN 24-010-05, DATED JULY 02, 2005, WHICH SHOULD BE REMOVED
FROM YOUR. THIS IS A COMPLETE REVISION AND NO ASTERISKS HAVE BEEN USED TO HIGHLIGHT REVISIONS.
SUBJECT:
FLASH: HVAC Automatic Temperature Control - Comfort Setting Improvements
OVERVIEW:
This bulletin involves selectively erasing and reprogramming the HVAC Automatic Temperature Control module (ATC) module with new software.
MODELS:
2005
(WK/WH)
Grand Cherokee
NOTE:
This bulletin applies to vehicles equipped with Automatic Temperature Control (sales code HAF) built prior to June 5, 2005 (MDH 0605XX) for
domestic market vehicles, or built prior to November 10, 2005 (MDH 111 1Xx) for international market vehicles.
SYMPTOM/CONDITION:
The new HVAC ATC module software corrects the following comfort setting conditions that the vehicle operator may experience:
^
Comfort Setting Drift. The HVAC temperature may slowly change (drift) from the comfort setting originally established by the customer. The slow
temperature change may be either towards cooler or warmer temperatures.
^
Comfort Setting Slow To Change When Adjusted. When the customer makes an adjustment to the comfort setting, the ATC is slow to respond to the
new comfort setting. The customer may need to adjust the comfort setting to full hot or full cold to effect the desired new comfort setting.
^
Comfort Setting Increments Too Small. When the customer makes an minor temperature adjustment to the comfort setting, the customer may notice
little or no change in temperature output.
^
Momentary Charge Of Cold Or Hot Air. When the comfort setting is in the maximum cold or maximum hot comfort setting, the ATC is in manual
control mode. When the customer makes a temperature adjustment to the comfort setting from one of these two maximum settings, the ATC enters its
automatic control mode. The customer may notice a momentary charge of cold or hot air when the comfort setting is moved from either the
maximum cold or hot comfort setting to any of the intermediate comfort settings.
DIAGNOSIS:
1.
If one of the above conditions are present, then use a StarSCAN(R) tool to read the current part number and the current software version level of
the HVAC ATC module.
a.
From the StarSCAN(R) tool "Home" screen, select "ECU View".
b.
Select "HVAC".
c.
Record the HVAC ATC module part number that is displayed.
d.
Record the current HVAC ATC module software version level.
2.
Is the current ATC module software version one of the following versions: 03.00.04, or 03.00.05, or 03.00.12, or 03.00.20, or 04.00.01, or
04.00.07?
a.
If YES >> then proceed to the next step.
