U0103: 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 U0103 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

15 complaints filed with NHTSA mention U0103, 14 of them since 2015, across 10 different models. The component owners most often filed it under: electrical system.

Manufacturer service bulletins that name U0103

22 technical service bulletins and manufacturer communications filed with NHTSA mention U0103, from 6 makes. A bulletin means the manufacturer has documented a known cause or a fix procedure for that model. Examples:

  • JEEP GRAND CHEROKEE (2023, 2024, 2025), bulletin 11010695: SHIFTER The service shifter message comes on in the cluster and the lever gets stuck in park "P" and it can be present the follwoing DTC: - U11E3 - TCM Lost communication with ESM on D-PT CAN - U0103 - Lost communication…
  • CHRYSLER PACIFICA PLUG-IN HYBRID (2023, 2024), bulletin 11002527: Shifter Binding Or "Service Shifter" Message On The Cluster. DTSs U11E3, U0103, U1267 For Loss Of Communication With The Electronic Gear Shift Module
  • RAM 1500 (2023, 2024), bulletin 11005338: Shifter Binding Or "Service Shifter" Message On The Cluster. Scan the vehicle for DTCs. If one or more of the following are set, proceed to Repair. - U11E3 - TCM Lost Communication with ESM on D-PT CAN - U0103 - Loss Com…
  • LINCOLN AVIATOR (2020, 2021), bulletin 10183390: Some 2020-2021 Aviator and Explorer vehicles may experience an intermittent no crank, inoperative remote start, and/or an illuminated wrench light with diagnostic trouble codes (DTCs) P07E4, B135C and/or U0103. This may …
  • FORD EXPLORER (2020, 2021), bulletin 10183390: Some 2020-2021 Aviator and Explorer vehicles may experience an intermittent no crank, inoperative remote start, and/or an illuminated wrench light with diagnostic trouble codes (DTCs) P07E4, B135C and/or U0103. This may …
  • FORD MUSTANG MACH E (2021), bulletin 10203653: Some 2021 Mustang Mach-E vehicles built on or before 09-Sep-2021 may exhibit an illuminated powertrain malfunction indicator (wrench) lamp and/or display the message Shift System Fault  Service required with DTC U0103:8…

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.