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).
L1026
Service Bulletin/Repair Instructions
SERVICE BULLETIN L1026: TECH TIP 002 - S2 12 VOLT BATTERY BEST PRACTICES. PURPOSE: Initial Release. This bulletin informs dealers of best practices for diagnosing a LiveWire S2 vehicle that presents a depleted or fully-discharged 12 V battery and making sure contributing issues are identified. Use this bulletin’s troubleshooting guidance to help identify contributing issues affecting 12 V battery health. A depleted or fully discharged 12v battery may be the result of other systems or components affecting 12 V battery health. Or it may be the result of expected behavior relating to certain conditions the 12 V battery was exposed.
L1020
Service Bulletin/Repair Instructions
SERVICE BULLETIN L1020: S2 COOLING SYSTEM FILL AND BLEED TIPS. PURPOSE: Initial Release. This bulletin provides dealers with best practices for filling and bleeding the cooling system on S2 models after component replacement. This can help prevent customer vehicle returns due to unpurged air in the cooling system. The most common symptom of this is the turtle icon illuminating on the instrument module after only a few minutes of riding.