Common DOT violations, explained
Every page below covers one cite from FMCSA's official SMS violation list (version 3.21): what the inspector meant, the official severity weight, which CSA category it feeds, whether it follows the driver, and what to do next. Got a different code? Look up any of the 2,412 codes free.
Vehicle Maintenance
- 393.9Inoperable Required Lampsev 2/10
- 393.9TSInoperative turn signalsev 6/10
- 393.75(a)(3)Tire-flat and/or audible air leaksev 8/10
- 393.75(b)Tire-front tread depth less than 4/32 of inch on a major tread groovesev 8/10
- 393.75(c)Tire-other tread depth less than 2/32 of inch measured in a major tread groovesev 8/10
- 393.47(e)Brake Out of Adjustment - Roto, Clamp (Short & Long), DD-3, or Boltsev 4/10
- 393.45Brake tubing and hose adequacysev 4/10
- 396.3A1BBrakes (general) Explain:sev 4/10
- 396.5B-LLubrication - Oil or grease leaksev 3/10
- 393.60(c)Windshield - Damaged or Discoloredsev 1/10
- 396.17(c)Operating a CMV without proof of a periodic inspectionsev 4/10
- 392.2-SLLMFState/Local Laws - Wheel (mud) flaps missing or defectivesev 1/10
HOS Compliance
- 395.8Record of Duty Status violation (general/form and manner)sev 1/10
- 395.8F01Drivers record of duty status not currentsev 5/10
- 395.8(e)False report of drivers record of duty statussev 7/10
- 395.8A-ELDELD - No record of duty status (ELD Required)sev 5/10
- 395.8A-NON-ELDNo record of duty status when one is required (ELD Not Required)sev 5/10
- 395.22AOperating with a device that is not registered with FMCSAsev 5/10
- 395.3A2-PROPDriving beyond 14 hour duty period (Property carrying vehicle)sev 7/10
- 395.3A1R11 hour rule violation (Property)sev 7/10
Unsafe Driving
- 392.2-SLLS2State/Local Laws - Speeding 6-10 miles per hour over the speed limitsev 4/10
- 392.2-SLLS3State/Local Laws - Speeding 11-14 miles per hour over the speed limitsev 7/10
- 392.2-SLLS4State/Local Laws - Speeding 15 or more miles per hour over the speed limitsev 10/10
- 392.2-SLLSWZState/Local Laws - Speeding work/construction zonesev 10/10
- 392.16Failing to use seat belt while operating a CMVsev 7/10
- 392.82(a)(1)Using a hand-held mobile telephone while operating a CMVsev 10/10
- 392.80(a)Driving a commercial motor vehicle while Textingsev 10/10
Driver Fitness
Controlled Substances/Alcohol
Codes, descriptions and severity weights verbatim from FMCSA's SMS Appendix A (retrieved 2026-09-06). Out-of-service criteria are CVSA's and not reproduced here.