U0104: 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 U0104 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

6 complaints filed with NHTSA mention U0104, 6 of them since 2015, across 4 different models. The component owners most often filed it under: forward collision avoidance: adaptive cruise control.

Most-reported models

VehicleComplaintsModel years reported
HONDA ODYSSEY32018, 2020

Manufacturer service bulletins that name U0104

36 technical service bulletins and manufacturer communications filed with NHTSA mention U0104, from 8 makes. A bulletin means the manufacturer has documented a known cause or a fix procedure for that model. Examples:

  • RAM 1500 (2025), bulletin 11008018: "Flash: Powertrain Control Module (PCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): P01…
  • JEEP GRAND CHEROKEE (2021), bulletin 10198368: Long Crank With Diagnostic Trouble Code (DTC) U0104 ? Lost Communication With Cruise Control Module, Set.
  • DODGE CHALLENGER (2021), bulletin 10222994: Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further inves…
  • DODGE CHARGER (2021), bulletin 10222992: Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further inves…
  • CHRYSLER 300 (2021), bulletin 10222991: Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the PCM with the latest available software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further inves…
  • CADILLAC ESCALADE (2017, 2018, 2019, 2020), bulletin 10173683: This Preliminary information communicates a customer concern ofIPC gauges inoperative or fluctuate, No Start,No Crank,SIR Light / Service Airbag Message, Service Suspension Message,Radio display blank, Steering Wheel Con…

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.