ATTENTION:
GENERAL MANAGER

q

PARTS MANAGER

q

CLAIMS PERSONNEL

q

IMPORTANT - All
Service Personnel
Should Read and
Initial in the boxes
provided, right.

SERVICE MANAGER

q

© 2021 Subaru of America, Inc. All rights reserved.

SERVICE BULLETIN
APPLICABILITY:

2019-21MY Forester

NUMBER: 09-75-21

SUBJECT:

DTC P0128 / Coolant Thermostat
(Engine Coolant Temperature Below Thermostat
Regulating Temperature)

DATE:

07/28/21

INTRODUCTION:
This bulletin announces the availability of NEW reprogramming files to correct DTC P0128.
This DTC may be set while the engine is below operating temperature and the vehicle is driven in
continuous downhill or descending road conditions. This new logic optimizes the coolant temperature
data to provide the ECM (Engine Control Module) with a precise value. If DTC P0128 is current or
stored within the ECM, the following programing file is to be installed.

PRODUCTION CHANGE INFORMATION:
This logic has been installed on all Forester models starting with VIN MH539229.

PAK FILE APPLICABILITY:
File
Number

Model

PAK File Name

Decryption
Keyword

New ECM CID
Number

1

2019MY
FORESTER

22765AL823.pak

D1F47BC4

XE1F501A

2

2020MY
FORESTER

22765AN462.pak

279103B2

XE1M301a00G

3

2021MY
FORESTER

82201AR671.pak

EBC190D9

XE1P101a00G

This reprogramming file is included in the July 2021 SSM4 software update.

CAUTION: VEHICLE SERVICING PERFORMED BY UNTRAINED PERSONS COULD
RESULT IN SERIOUS INJURY TO THOSE PERSONS OR TO OTHERS.
Subaru Service Bulletins are intended for use by professional technicians ONLY. They
are written to inform those technicians of conditions that may occur in some vehicles,
or to provide information that could assist in the proper servicing of the vehicle. Properly
trained technicians have the equipment, tools, safety instructions, and know-how to
do the job correctly and safely. If a condition is described, DO NOT assume that this
Service Bulletin applies to your vehicle, or that your vehicle will have that condition.

Subaru of America, Inc. is
ISO 14001 Compliant
ISO 14001 is the international standard for
excellence in Environmental Management
Systems. Please recycle or dispose of
automotive products in a manner that is friendly
to our environment and in accordance with all
local, state and federal laws and regulations.

Continued...
Bulletin Number: 09-75-21; Date: 07/28/21

Page 1 of 3

SERVICE PROCEDURE / INFORMATION:
REMINDER: Customer satisfaction and retention starts with performing quality repairs.
•

Reprogram the ECM following the normal FlashWrite procedure.

Subaru of America, Inc. (SOA) highly recommends connecting either the Subaru Midtronics
DCA8000 Dynamic Diagnostic Charging System or the Subaru Midtronics GR8-1100 Diagnostic
Battery Charger to the vehicle and utilizing the Power Supply Mode feature anytime a vehicle control
module is being reprogrammed. Once the Midtronics charger is connected to the vehicle, if the
battery is fully charged, it takes less than three (3) minutes to boot-up the charger, select the Power
Supply Mode, and have the battery voltage stabilized and ready for reprogramming.

NOTES:
•

For instructions on using the power supply mode, reference the applicable User Manual for the
Midtronics DCA-8000 Dynamic Diagnostic Charging System and the Midtronics GR8-1100
Diagnostic Battery Charger on STIS.

•

Confirm all electrical loads such as lights, audio, HVAC, seat heaters, and rear defroster are all
switched OFF before setting up the charger for Power Supply Mode.

•

Select the correct battery type (Flooded, EFB, Gel, AGM or AGM Spiral).

•

Input the CCA which matches the vehicle’s battery. NOTE: OE and replacement batteries have
different CCA ratings. Always confirm the battery’s CCA rating before proceeding.

•

If using a DCA-8000 Dynamic Diagnostic Charging System, set the power supply voltage to 13.5
volts.

•

DO NOT connect the DST-i or SDI until the Power Supply mode function has completed its
battery test mode and the Charging Voltage has dropped to and shows a steady 13.5 Volts on the
display.

•

Once Power Supply Mode reaches a steady 13.5 volts, connect the DST-i or SDI to the OBD
connector and proceed with initiating the normal FlashWrite reprogramming process.

•

Amperage will fluctuate based upon the vehicle’s demand for power. NOTE: If the voltage rises
beyond 14V while programming is in process, the procedure will abort. This can indicate a need
to test or charge the vehicle battery before any further attempt at programming is made.

REMINDER: If the DCA-8000 or GR8-1100 indicates the vehicle’s battery must be charged, charge
the battery fully before proceeding to reprogram the vehicle while using the Power Supply Mode.

Continued...
Bulletin Number: 09-75-21; Date: 07/28/21

Page 2 of 3

NOTE: Control module failures resulting from battery discharge during reprogramming are not a
matter for warranty. Should any DTCs reset after the reprogramming update is performed, diagnose
per the procedure outlined in the applicable Service Manual.
VERY IMPORTANT:
This information is applicable to the Subaru Midtronics DCA-8000 Dynamic Diagnostic Charging
System and the Subaru Midtronics GR8-1100 Diagnostic Battery Charger ONLY. It does not apply to
any other brand / type of “generic” battery charger whatsoever. ONLY the DCA-8000 and the GR81100 and their Power Supply Mode feature have been tested and approved by SOA.

WARRANTY / CLAIM INFORMATION:
For vehicles within the Basic New Car Limited Warranty period, this repair may be submitted using
the following claim information:
Labor Description

Labor Operation #

Fail Code

Labor Time

MFI OBDII ECM Reprogramming

A455-288

UPG-48

0.4

IMPORTANT: Always note the original Calibration Identification number (CID) the vehicle came in
with on the repair order before reprogramming and, make sure to list the NEW CID for any newlyinstalled programming (as confirmed from the actual control module AFTER installation). The
NEW CID MUST also be noted on the repair order as this information is required for entry in the
Miscellaneous Detail field during claim submission.

NOTE: The pak file listings provided in this bulletin are the latest available at the time of publishing.
Updates are often released thereafter without revision to the original bulletin. For this reason, it is
critical to always have the latest version of Select Monitor software installed on your system. You
can confirm if a later version is available by entering the CID listed in this bulletin into FlashWrite.
If a newer CID is shown as available in FlashWrite, reprogram using that file.

IMPORTANT REMINDERS:
•

SOA strongly discourages the printing and/or local storage of service information as previously
released information and electronic publications may be updated at any time.

•

Always check for any open recalls or campaigns anytime a vehicle is in for servicing.

•

Always refer to STIS for the latest service information before performing any repairs.

Bulletin Number: 09-75-21; Date: 07/28/21

Page 3 of 3