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TCM Reprogramming Files/Engine Speed Drop (16-147-24)

Publication date: 2024-02-06
Reference number: 16-147-24

TCM REPROGRAMMING FILES/ENGINE SPEED DROP

TCM REPROGRAMMING FILES/ENGINE SPEED DROP

TECHNICAL SERVICE BULLETIN

Reference Number(s): 16-147-24, Date of Issue:  February 06, 2024
SUBARU: 2019-21MY Forester

APPLICABILITY

2019-21MY Forester

INTRODUCTION

This bulletin announces availability of reprogramming files to optimize the Transmission Control Module (TCM). The new files will address cases of possible engine speed drop when the engine is restarted with the auto start/stop function. The new software optimizes the engine cranking speed monitoring program of the TCM. If this symptom is reported by a customer, reprogram the TCM following service procedures outlined in this bulletin.

PAK FILE APPLICABILITY

Model Specification File Description Old Part Number Decryption Keyword New CID
19-21MY FORESTER 2.5L NA, CVT 30919AG023.pk2 30919AG020
30919AG021
30919AG022
0EFC359E S1F66663
19-21MY FORESTER 2.5L NA, CVT 30919AG033.pk2 30919AG030
30919AG031
30919AG032
AF5A4C1D S1F64663

SERVICE PROCEDURE/INFORMATION

REMINDER:  Customer satisfaction and retention starts with performing quality repairs.

Subaru of America, Inc. (SOA) highly recommends utilizing either the Subaru Midtronics DCA8000 Dynamic Diagnostic Charging System or the Subaru Midtronics GR8-1100 Diagnostic Battery Charger to the vehicle in 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 will take 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.

NOTE:
  • 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 (Enhanced Flooded, Flooded, 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 DST-010 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 DST-010 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 14 Volts 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.
  • ALWAYS set the power supply voltage to 13.5 Volts when using Power Supply Mode. NEVER turn the ignition switch on when charging at voltages 15 Volts or higher.

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 GR8-1100 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
TCM Reprogramming A860-732 0.4 MJZ-48
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 newly-installed 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: