Technical Service Bulletin (TSB)
Flash: Powertrain Control Module (PCM) Updates
REFERENCE:

TSB: 18-070-24
GROUP: 18 - Vehicle Performance

Date:

September 14, 2024 REVISION: ––

VEHICLES
AFFECTED:

2023 (WL) Jeep Grand Cherokee/Grand Cherokee L
This bulletin applies to vehicles equipped with the 2.0L I4 DOHC DI
Turbo PHEV Engine (Sales Code ECX) and 8-Spd Auto 8P75PH PHEV
Transmission (Sales Code DFY).

MARKET APPLICABILITY:
NA

IAP

EE

MEA

SA

CH

CUSTOMER
SYMPTOM:

Customers must experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation
the technician must find one or more of the following Diagnostic Trouble Codes (DTC)s have been set:
● P0629 - Fuel Pump Control Circuit High.
● P0171 - Fuel system Lean.
● P0087 - Fuel Rail Pressure Too Low - Bank 1.
Customers may also experience the following:
● Vehicle will not start.
● The Instrument Cluster Panel (ICP) unable to calculate the instantaneous fuel economy under heavy
acceleration.
● The oxygen sensor can give incorrect values when entering EV mode. False fault detection (MIL on) is
possible when this event occurs.
● The rear half shafts are damaged due to accelerating in drive with the Electronic Parking Brake (EPB)
applied.

CAUSE:

PCM software

REPAIR SUMMARY:
This bulletin involves updating the PCM with the latest available software.
CLAIMS DATA:

Labor Operation No:
18-19-87-PP

Failure Code

Labor Description
Powertrain Module (PCM)
- Reprogram
(0 - Introduction)
CC

Skill Category
1 - Engine Repair And
Performance
Customer Concern

Labor Time
0.2 Hrs.

B08 FSAR-TSB-4397

-2-

RELATED TIME ALLOWANCE:

Labor Operation No:
18-19-87-52

Labor Description
wiTECH Routine to
Disable/Enable HV
Battery Contactors for
Service; Includes 5
Minute Waiting Period
(0 - Introduction)

Skill Category
6 - Electrical and Body
Systems

Labor Time
0.2 Hrs.

The dealer must use failure code CC with this Technical Service Bulletin.
● If the customer’s concern matches the SYMPTOM identified in the Technical 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 Technical Service Bulletin flash/reprogramming conditions.
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 DTCs or symptom conditions, other
than the ones 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 any of the symptoms listed above in the customer symptom section, perform the
Repair Procedure.
SPECIAL TOOLS/EQUIPMENT:

Description
wiTECH or Equivalent

Ref. No.
–

Notes
–

REPAIR PROCEDURE:
WARNING!
● Before performing the software reprogramming, it is necessary to make the vehicle safe.
● When performing repairs that directly involve or imply possible contact with live high voltage
components/systems, the technician must ensure that the power supply of the high-voltage system
is disconnected throughout the operation.
● Only specifically trained technicians qualified to perform repairs on vehicles with high voltage
systems under current national laws/regulations are authorized to work on the vehicle.
● Before performing any diagnostic repair work on the vehicle, carefully read and comply with
the general instructions for working safely on hybrid/electric vehicles and use suitable general
equipment and Personal Protective Equipment (PPE).
NOTE: The vehicle must not be connected to a high voltage charger when performing software
updates.
NOTE: Install a battery charger to maintain a 12 volt system voltage.
NOTE: If this flash process is interrupted/aborted, the flash should be restarted.

-3-

B08 FSAR-TSB-4397

1. Disable HV Battery Contactors using wiTECH - Go to the Misc Functions tab --> Select Disable HV Battery
Contactors --> then follow the wiTECH prompts.
2. Use wiTECH to confirm that the contactors are open and waiting five minutes. If the contactors do not
open turn the ignition on then off. Once successful a note will appear on the wiTECH screen indicating the
contactors are open.
3. Reprogram the PCM with the latest software. Detailed instructions for flashing control modules using the
wiTECH Diagnostic Application are available by selecting the application ”HELP” tab.
4. Clear all 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.
5. Enable HV Battery Contactors using wiTECH - Go to the Misc Functions tab --> Select Enable HV Battery
Contactors For Service--> then follow the wiTECH prompts.
POLICY:
Reimbursable within the provisions of the warranty.
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.