What 393.11TL means in plain language
FMCSR 393.11TL targets commercial motor vehicles that hit the road with lighting equipment or reflectors that are either missing entirely or not functioning the way the regulations require. In short, if your truck can't be adequately seen — by other drivers, by law enforcement, or by anyone sharing the road — you're exposed to this citation.
The "TL" variant specifically addresses trailers in the lighting device and reflector family of requirements. Think marker lights, clearance lights, reflective devices, and similar equipment designed to make the trailer visible from the front, sides, and rear under any conditions. If any of that hardware is absent, broken, or obscured, an inspector has grounds to write this up.
This is not an obscure edge case. It is one of the most routinely observed deficiencies in roadside inspections, and it applies to equipment that is easy to overlook during a rushed pre-trip — especially after dark, in dirty conditions, or when mud and road grime have caked over reflective surfaces.
What our enforcement data actually shows
Across our database of 13 million+ inspections, 393.11TL has accumulated 23,327 all-time citations, placing it at #120 out of 3,036 FMCSR codes by citation volume. That is a high-traffic violation by any measure. In the last 12 months alone, our inspection records show 14,955 citations issued under this code. In just the last 90 days, 3,295 citations were recorded — a pace that reflects consistent, active enforcement rather than a temporary blitz.
Here is the number that should give you some relief: the all-time out-of-service rate for 393.11TL is 0.0%. Out of 23,327 citations, only 2 vehicles were placed out of service. That means the overwhelming majority — 23,325 — were cited and allowed to continue operating. For context, the all-FMCSR average OOS rate across all codes is 31.4%. This code sits essentially at zero by comparison. You are not being shut down at the roadside for a 393.11TL citation in any realistic scenario.
That said, 393.11TL carries a CSA severity weight of 3, which means it does score against your Safety Measurement System (SMS) profile. It won't shut you down today, but it accumulates — and fleets that collect multiple lighting violations will see their Vehicle Maintenance BASIC score climb.
Looking at the monthly trend in our data, citation volume has been running between 1,200 and 1,487 citations per month for the past several months, with February 2026 hitting the highest single-month count at 1,487 citations. Enforcement is steady and shows no sign of tapering off.
Who gets cited most
Our inspection records show Texas dominating the geographic picture by a wide margin. In the last 180 days, TX logged 6,622 citations for 393.11TL with a 0.0% OOS rate. Iowa came in second at 524 citations, also at 0.0% OOS. Illinois ranked third at 30 citations, again with no vehicles placed out of service. The OOS rates across these top states are uniform — none of them are pulling trucks for this violation — but the raw volume in Texas is strikingly higher than anywhere else in our database.
On the carrier side, our data shows fleets such as BUOYANT ENERGY LLC (USDOT 3343091) with 35 all-time citations and AGGREGATE HAULERS I L P (USDOT 1021485) with 31 citations appearing at the top of the citation count list. Volume at that level across a fleet typically points to a systemic gap in pre-trip inspection culture or maintenance scheduling, not isolated incidents.
Vehicle make data in our database shows Freightliner (FRHT) leading with 7,344 all-time citations under this code, followed by Kenworth (KW) at 3,775 and Peterbilt (PTRB) at 3,766. These are the most common platforms on the road, so the numbers reflect market share as much as anything — but if you run one of these rigs, you are in the most-cited segment.
How severe is this compared to similar codes
Looking at peer codes within the Vehicle Maintenance category in our database, 393.11TL is a lower-severity citation compared to most of its neighbors.
393.9(a) — Inoperable required lamps has 660,737 all-time citations and carries a 15.4% OOS rate. That is a dramatically different enforcement outcome than 393.11TL's 0.0% rate, and the volume is roughly 28 times higher. If an inspector finds an inoperable lamp rather than just a missing or inadequate reflector, the likelihood of being placed out of service increases substantially.
396.3(a)(1) — Inspection/repair/maintenance - general has 236,919 citations and a 45.3% OOS rate — meaning nearly half of all vehicles cited under that code are shut down on the spot. That is the difference between a maintenance documentation failure and what 393.11TL represents.
393.11 — Lighting devices/reflectors (the non-TL parent code) has 179,734 citations and a 1.8% OOS rate, which is still well above the 0.0% rate seen for 393.11TL specifically.
The pattern is clear: 393.11TL is a citation that hurts your CSA score without pulling you off the road, but the codes it travels with — and the ones just above it in severity — can absolutely shut a truck down.
How to avoid it
The co-occurring violation data in our database is the most actionable signal here. In the last 90 days, 393.11TL appeared alongside 393.9 (Inoperable Required Lamp) in 1,441 shared inspections, meaning inspectors who find one lighting problem almost always find another. A thorough lighting walk-around catches both. Here is what that looks like in practice:
- Walk every marker and clearance light on the trailer before you move. With 610 shared inspections between 393.11TL and its close variant 393.11TU, inspectors are clearly checking the entire lighting assembly, not just one side.
- Check reflectors for mud, impact damage, and mounting integrity. Reflectors are easy to miss in daylight and during a fast pre-trip. Wipe them down and physically confirm they are seated and intact.
- Test all turn signals, not just headlights. Our data shows 393.9TS (Inoperative turn signal) co-occurring in 454 shared inspections. If a turn signal is dead, it is often caught in the same stop that produces a 393.11TL citation.
- Carry your most recent periodic inspection documentation. Code 396.17C appeared alongside 393.11TL in 562 shared inspections. If you cannot show proof of periodic inspection, you hand the inspector a second violation on a silver platter.
- Inspect the windshield. 393.78 (Windshield condition defective) appeared in 766 shared inspections with this code. Inspectors doing a full vehicle check are looking at the whole truck, not just the lights.
- Check fuel system connections while you're under the trailer. 396.5B (Fuel system leak) co-occurred in 476 shared inspections. If you're already doing a proper trailer walk-around, a quick look at fuel line connections costs nothing and prevents a separate violation.
Freightliner, Kenworth, and Peterbilt operators account for the largest share of citations in our database. If you run any of these platforms, build lighting checks into a written pre-trip checklist and do not shortcut it regardless of weather or schedule pressure. The citation is preventable with ten minutes of attention before the wheels turn.