Hyundai TSB #21-BE-008H
2018 Hyundai Sonata
Affected Component: ELECTRICAL SYSTEM
- Summary
- Certain vehicles may experience 504 Time Out errors when using the Blue Link Mobile App. When asked to provide Modem Information (IMEI/USIM), the Head Unit (HU) displays all zeros. This bulletin describes the procedure to update the Head Unit Software to correct this condition.