Technical service bulletins are instructions a manufacturer sent its dealers about a known fault. They are not recalls and the work is usually not free, but they are the clearest signal of a problem the manufacturer already knows about.
M1490
Service Bulletin/Repair Instructions
SERVICE BULLETIN M1490 (V 26.0.2): DIGITAL TECHNICIAN II - UPDATES AND RELEASE NOTES. PURPOSE: Revision. This bulletin informs dealers that Harley-Davidson has made a software update to Digital Technician II (DT II). DIGITAL TECHNICIAN II (PART NUMBER: HD-48650). New Software Update Version 26.0.2. Release Date: Week of November 18, 2025. New Features, Changes. 2026 Vehicles, 2025 Softail and LiveWire S2DM/MH/AP EV3. NOTE: Digital Technician II (DT II) supports additional Harley-Davidson motorcycle models and model years outside of those listed.
M1391A
Service Bulletin/Repair Instructions
SERVICE BULLETIN M1391A (REVU): MIDTRONICS GRX-3110 AND DCA-8000 SOFTWARE. PURPORSE: Revision U. The purpose of this bulletin is to inform the dealer network that a software update to the GRX-3110 and DCA-8000 is now available. DYNAMIC DIAGNOSTIC CHARGER SYSTEM (PART NUMBER: DCA-8000). [Rev U] Added: Description of improvements made to the testing algorithm for GRX software Version P and DCA-8000 software Version E.
PAB1171
Service Bulletin/Repair Instructions
GENUINE MOTOR PARTS AND ACCESSORIES BULLETIN PAB1171 (REV B): SOFTWARE UPDATE FOR SCREAMIN EAGLE PRO STREET TUNER. PURPOSE: Revision B. Updated: Summary. The App has returned to the Apple App Store. This bulletin informs dealers that a recent software update to the Screamin' Eagle Pro Street Tuner application will require the use of a Personal Computer (PC) to complete a Bluetooth Communication Interface (BCI) firmware update.
M1684
Service Bulletin/Repair Instructions
SERVICE BULLETIN M1684: MARKET SPECIFIC BATTERY INTRODUCTION. PURPOSE: Initial Release. This bulletin informs dealers of the availability of new batteries for new Original Equipment (OE) vehicle production and in the Parts and Accessories (P&A) catalog. Availability of the new Absorbed Glass Mat (AGM) batteries will vary by market and will be transitioning over the next few months. NOTE: The ring terminal screws are not compatible between Leoch and East Penn batteries. The new batteries will include new ring terminal screws, which must be used. The ring terminal screws from the old battery need to be discarded.