2400721

NUMBER:
GROUP:
DATE:
24-007-21
24 - Heating and Air
Conditioning
May 21, 2021
This bulletin is supplied as technical information only and is not an authorization for repair. No part of this publication may be reproduced, stored in a retrieval system, or
transmitted, in any form or by any means, electronic, mechanical, photocopying, or otherwise, without written permission of FCA US LLC.
This bulletin supersedes Technical Service Bulletin (TSB) 24-006-19, date of issue June 19,
2019, which should be removed from your files. All revisions are highlighted with
**asterisks** and include additional model years and vehicles, Symptom/Conditions, software
enhancement and LOP.
SUBJECT:
Flash: HVAC Diagnostic and System Updates
OVERVIEW:
This bulletin involves reprogramming the HVAC control module with the latest available software.
MODELS:
**2020 - 2021
(JT)
Jeep Gladiator**
2018 - **2021**
(JL)
Jeep Wrangler
NOTE: This bulletin applies to vehicles within the following markets/countries: North
America, LATAM, APAC and EMEA.
NOTE: **This bulletin applies to vehicles built on or before September 30, 2020 (MDH
0930XX) equipped with Air Conditioning (Sales Code HAA) or Air Conditioning
W/Auto Temp Control (Sales Code HAB)**.
SYMPTOM/CONDITION:
The customer may notice one or more of the following:
• **Intermittent change of smell or humidity level in vehicle.
• An intermittent blast of warm air when A/C is on.**
• Intermittent increase of outside air through the HVAC system.
**In addition, the following software enhancement is also available:
• Improvements for customer concerns of ’cabin too warm’, specifically in the mid ambient
temperature range 4.5-15.5 °C (40-60 °F).**
DIAGNOSIS:
Using a Scan Tool (wiTECH) with the appropriate Diagnostic Procedures available in
DealerCONNECT/Service Library, verify all related systems are functioning as designed. If symptom
conditions, other than the one listed above are present, record the issues on the repair order and
repair as necessary before proceeding further with this bulletin.
If the customer describes the symptom/condition listed above, perform the Repair Procedure.
24-007-21
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REPAIR PROCEDURE:
NOTE: Install a battery charger to ensure battery voltage does not drop below 13.2 volts. Do
not allow the charging voltage to climb above 13.5 volts during the flash process.
NOTE: If this flash process is interrupted/aborted, the flash should be restarted.
1. Reprogram the HVAC control module with the latest software. Detailed instructions for flashing
control modules using the wiTECH Diagnostic Application are available by selecting the
application’s “HELP” tab.
2. Cycle the ignition to “Off” and then back to “On”.
3. Clear all Diagnostic Trouble Codes (DTCs) that may have been set in any module due to
reprogramming. The wiTECH application will automatically present all DTCs after the flash and
allow them to be cleared.
POLICY:
Reimbursable within the provisions of the warranty.
TIME ALLOWANCE:
Labor Operation
No:
**18-50-10-AC
Description
Skill Category
Amount
Module, HVAC Control - Reprogram
(0 - Introduction)
7 - Air Conditioning and
Heating
0.2 Hrs.**
NOTE: The expected completion time for the flash download portion of this procedure is
approximately 3 minutes. Actual flash download times may be affected by vehicle
connection and network capabilities.
FAILURE CODE:
The dealer must use failure code CC with this Service Bulletin.
• If the customer’s concern matches the SYMPTOM/CONDITION identified in the Service
Bulletin, failure code CC is to be used.
• When utilizing this failure code the 3C’s (customer’s concern, cause and correction) must be
provided for processing Service Bulletin flash/reprogramming conditions.
CC
Customer Concern