NHTSA ID Number: 10199964
Manufacturer Communication Number: 09-77-21
TSB/Document Date: 2021-08-05
Summary
This bulletin announces the availability of ECM reprograming files to correct a possible lack of power and/or hesitation during acceleration at engine speeds of 1500-3500 rpm.
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:
2017-21MY Impreza 2.0L MT
2018-21MY Crosstrek 2.0L MT
NUMBER: 09-77-21
DATE: 07/28/21
SUBJECT:
Lack of Power / Hesitation During Acceleration
INTRODUCTION:
This bulletin announces the availability of ECM reprograming files to correct a possible lack of
power and/or hesitation during acceleration at engine speeds of 1500-3500 rpm. In some cases, the
knock sensor may detect crank shaft vibration causing the ECM to interpret it incorrectly as engine
knocking (pinging). This can result in incorrect ignition timing leading to a noticeable reduction or
delay in acceleration. This new logic enhances engine knocking detection by the ECM.
IMPORTANT NOTE: This bulletin ONLY applies to models equipped with manual transmissions.
PRODUCTION CHANGE INFORMATION:
This logic has been installed on all Crosstrek models as of staring VIN M936612.
The production change information for Impreza is TBD.
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: 09-77-21; Date: 07/28/21
Page 1 of 4
PAK FILE APPLICABILITY:
Model
Model Year
Specification
Pak File Name
Decryption
Keyword
New ECM CID
Number
17-18MY
2.0L NA AGS*
5MT
22765AJ59K.pak
9B767F3E
XH3J2C1C
17-18MY
2.0L NA
5MT
22765AK61K.pak
9DB28E88
XH3J2C1A
19MY
2.0L NA AGS*
5MT
22765AM64F.pak
EE846B14
XH3N601C
19MY
2.0L NA
5MT
22765AM65F.pak
D16FD4BA
XH3N601A
20MY
2.0L NA AGS*
5MT
22765AP11C.pak
149FBFC0
XE1M301C00G
20MY
2.0L NA
5MT
22765AP12C.pak
5D1CB56E
XE1M301A00G
21MY
2.0L NA AGS*
5MT
22765AP84B.pak
32AE558E
XE1P101C00G
21MY
2.0L NA
5MT
22765AP85B.pak
18875822
XE1P101A00G
18MY
2.0L NA
6MT
22765AJ617.pak
904A79D6
XH3J2C1E
19MY
2.0L NA
6MT
22765AM815.pak
C19070B4
XH3N601E
20MY
2.0L NA
6MT
22765AN932.pak
584FA350
XE1M301E00G
21MY
2.0L NA
6MT
22765AP921.pak
E833E79F
XE1P101E00G
Impreza
Crosstrek
These reprogramming files are included in the July 2021 SSM4 software
NOTE: AGS – Active Grille Shutter
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.
Continued...
Bulletin Number: 09-77-21; Date: 07/28/21
Page 2 of 4
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.
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.
Continued...
Bulletin Number: 09-77-21; Date: 07/28/21
Page 3 of 4
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: 09-77-21; Date: 07/28/21
Page 4 of 4
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TSB/Document ID: 09-77-21
Replacement Service Bulletin Number:
MFR Communication Date: 2021-07-28
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
NHTSA Components: ENGINE AND ENGINE COOLING
MFR Component System:
MFR Component Subsystem:
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