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 26.8.3): 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). Version Version 26.8.3, Release Date: Week of July 24, 2026. NOTE: Software version (26.4.3) will need to be manually installed only if current software version of DT II is (26.0.2). After (26.4.3) is manually installed, automatic updates will bring DT II to the latest software version. Refer to bulletin M1713 for instructions. New Features - Harley-Davidson: 2023-2024 Touring: Updated Electronic Control Module (ECM) calibration offerings. LiveWire: S2DM/MH/AP: Calibration bundle 10.2.28: Telematic Control Unit (TCU) reflash updates. Change: Vehicle Setup: Body Control Module (BCM) – Tire Pressure Monitoring System (TPMS) Replacement: Correct issue where tire size selections were not available. System Info – Auxiliary Load Controller (ALC): Added Bike configuration field. Data Items – Trike ECM: Improved display of Gear Position when in reverse. Amp – Added support for (Part No. 76001619).
M1722
Service Bulletin/Repair Instructions
SERVICE BULLETIN M1722 (REV A): EXHAUST SMOKE, OIL CARRY-OVER OR MILKY OIL (M8 MODELS WITH TRANSMISSION-MOUNTED BREATHER). PURPOSE: Revision A. Purpose for Service Bulletin. This bulletin informs dealers about: • The cause and effects of moisture in engine oil. • Service Manual troubleshooting updates for Milwaukee-Eight engines with the transmission-mounted breather, that have symptoms of moisture in oil and the best practices to avoid creating such instances. • New Job Time Code (JTC 3017 Diagnose Oil Carryover/Moisture) for service manual troubleshooting.
M1721
Service Bulletin/Repair Instructions
SERVICE BULLETIN M1721: UPDATES TO 2026 SOFTAIL SERVICE MANUAL. PURPOSE: Initial release. This bulletin informs dealers that the Regular Service Intervals table (pages 2-4 and 2-5) located within the printed 2026 Softail Service Manual > Maintenance > Maintenance Schedule section is incorrect. The table in the digital manual on Service Information Portal (SIP) is correct, as are the Maintenance Interval Checklists within the AMP system. Any printed Service Manuals ordered after March 2, 2026 contain the corrected tables.
M1679
Service Bulletin/Repair Instructions
SERVICE BULLETIN M1679: AFTERMARKET EXHAUST HEADER DEBRIS. PURPOSE: Initial release. This bulletin informs dealers that Harley-Davidson has identified instances of premature engine failure due to abrasive particle wear, specifically from debris inside new aftermarket exhaust headers. Recent evaluations have identified that certain newly manufactured exhaust headers may contain residual hard particles that, if not removed prior to installation, can migrate through the engine system and cause accelerated component wear or severe mechanical damage.
M1713
Service Bulletin/Repair Instructions
SERVICE BULLETIN M1713 (REV C): DTII UPDATE PROCEDURE FOR SOFTWARE VERSION (26.4.3). PURPOSE: Revision C. This bulletin informs dealers that an issue was discovered in the Digital Technician II (DT II) software version (26.0.2), released on November 18, 2025. The issue prevents automatic software updates to be installed on your DT II computer. A manual installation of the latest DT II software version (26.4.3) will need to be performed if current DT II software version is (26.0.2), to allow future automatic updates. If a manual update to (26.1.5) or (26.3.2) has previously been completed, DT II will automatically update to (26.4.3) and no additional action is needed.. Revision C. Updated: Purpose for Service Bulletin and Required Dealer Action. Updated to Software Version (26.4.3).
PAB1174
Service Bulletin/Repair Instructions
SERVICE BULLETIN PAB1174 (REV A): SCREAMIN EAGLE STAGE KITS (I-IV) FITMENT HOLD. PURPOSE: Revision. This bulletin informs dealers that Harley-Davidson has lifted the hold for the Screamin' Eagle Pro Street Tuner and software for certain 2026 vehicles. Updated: Purpose for Parts and Accessories Bulletin and Summary. Updated: Purpose for Parts and Accessories Bulletin and Summary, Update software availability.
M1697
Service Bulletin/Repair Instructions
SERVICE BULLETIN M1697: 2026 SOFTAIL ENGINE OIL DIPSTICK CHANGE. PURPOSE: Initial Release. This bulletin informs dealers that all 2026 Softail models will utilize a new oil level check procedure and be equipped with a new Engine Oil Fill Plug/Dipstick (Part No. 62700380). The new plug/dipstick has a different (Part No. 62700380) whereas the old plug/dipstick is (Part No. 62700226). Along with the new plug/dipstick, there is a new Check Engine Oil Level procedure. See the latest Owner’s Manual or Service Manual on Service Information Portal (SIP).