Violation codes / 393.19
49 CFR 393 · Parts and accessories393.19
Inoperative/Defective Hazard Warning Lamp
What the rule actually says
This violation cites 49 CFR 393.19, hazard warning signals. The regulation reads:
The hazard warning signal operating unit on each commercial motor vehicle shall operate independently of the ignition or equivalent switch, and when activated, cause all turn signals required by § 393.11 to flash simultaneously.
49 CFR 393.19, Hazard warning signals. Read the full section on eCFR
Quoted verbatim from the Electronic Code of Federal Regulations. Nothing here is a paraphrase, and nothing here is legal advice on a citation.
How often this comes up
This violation was recorded 30,646 times across the roadside inspections in the FMCSA file, making it the 107th most frequently cited code. Whether a given instance puts a vehicle or driver out of service is decided at the roadside by the inspector, not by the code itself, so the same violation can end a trip or simply be noted.
It sits under 49 CFR Part 393, which covers parts and accessories. To see it in context, look up a carrier and read its inspection history: the same code appearing repeatedly is a different signal from a single occurrence.
Look up a carrier's inspection record
Other parts and accessories violations
- 393.9 Inoperable Required Lamp
- 393.47E Brake Out of Adjustment - Roto, Clamp (Short…
- 393.75A3-TAOL Tires - All others, leaking or inflation les…
- 393.78 Wipers - Inoperative / missing / damaged wip…
- 393.9TS Inoperative turn signal
- 393.9A-LIL Lighting - Identification lamp(s) inoperativ…
- 393.75A3 Tire-flat and/or audible air leak
- 393.95A No/discharged/unsecured fire extinguisher
- 393.95F Emergency Equipment - Stopped vehicle warnin…
- 393.60C Windshield - Damaged or Discolored
- 393.55E-B Air Brake - ABS malfunction lamp defective o…
- 393.45B2UV Brake Hose or Tubing Chafing and/or Kinking …
Counts are from the FMCSA Inspections and Violations file via data.transportation.gov. This describes how the violation is recorded, and is not legal advice on a citation.