U2100: owner reports and bulletins

Network / communication. We haven't written the explanation for this code yet. Below is what owners and manufacturers have filed with NHTSA.

Got U2100 on your scanner? Tell the mechanic your year, make, model and any symptoms and you'll get the likely cause and what to check first. Ask about this code.

What owners report to NHTSA

9 complaints filed with NHTSA mention U2100, 3 of them since 2015, across 4 different models. The component owners most often filed it under: electrical system.

Most-reported models

VehicleComplaintsModel years reported
CHEVROLET COBALT62005, 2006

Manufacturer service bulletins that name U2100

35 technical service bulletins and manufacturer communications filed with NHTSA mention U2100, from 4 makes. A bulletin means the manufacturer has documented a known cause or a fix procedure for that model. Examples:

  • FORD MUSTANG MACH E (2021, 2022, 2023, 2024), bulletin 11008698: Some 2021-2024 Ford and Lincoln vehicles may exhibit diagnostic trouble codes (DTCs) U2100 and/or U3002 stored in the cruise control module (CCM), side obstacle detection control module LH (SODL), side obstacle detection…
  • LINCOLN CORSAIR (2023, 2024), bulletin 11008698: Some 2021-2024 Ford and Lincoln vehicles may exhibit diagnostic trouble codes (DTCs) U2100 and/or U3002 stored in the cruise control module (CCM), side obstacle detection control module LH (SODL), side obstacle detection…
  • FORD TRANSIT (2022, 2023), bulletin 10224332: Some 2023 Ford Transit with 12 inch center display screen built on or after 01-Sep-2022 may exhibit inoperative connected vehicle features, such as the activate button missing in FordPass, unable to connect wirelessly to…
  • LINCOLN AVIATOR (2020, 2021, 2022, 2023), bulletin 10236334: Some 2020-2023 Aviator vehicles equipped with air suspension may exhibit a drive malfunction and/or suspension fault message in the instrument panel cluster (IPC) with diagnostic trouble codes (DTCs) B1041 and U2100 stor…
  • FORD F-650 SD (2023), bulletin 10236687: Some 2023 F-Super Duty vehicles equipped with SYNC 4 may require a replacement of the body control module (BCM) for various concerns. After programmable module installation (PMI) of the new BCM, diagnostic trouble codes …
  • FORD F-750 SD (2023), bulletin 10237586: Some 2023 F-Super Duty vehicles equipped with SYNC 4 may experience programming errors after a replacement of the body control module (BCM) for various concerns. After programmable module installation (PMI) of the new BC…

Sources: NHTSA Office of Defects Investigation complaint database and manufacturer communications file, snapshots September 2026. A complaint or bulletin that mentions a code is a report about that vehicle, not a statement that the code has one cause.