What 393.11B-CSLRR means in plain language
This violation is written when an inspector determines that your commercial motor vehicle is missing required lighting equipment or has reflectors that don't meet federal standards. It covers the full range of exterior lighting and reflective hardware—side marker lamps, clearance lights, conspicuity reflectors, and similar components that are mandated by Part 393 of the FMCSRs.
The underlying rule requires that every CMV operating on public roads carry all required lighting devices and reflectors in proper working condition. If one or more of those components is absent, damaged to the point of non-compliance, or otherwise inadequate, an inspector can issue this citation on the spot.
Importantly, the suffix "CSLRR" identifies a specific sub-category within the broader 393.11B family—related to required reflectors on the sides of the vehicle. This matters because inspectors often cite multiple sub-variants of 393.11B during a single stop, meaning your inspection report may list several lighting-family codes alongside this one.
What our enforcement data actually shows
Across our inspection database, 393.11B-CSLRR has accumulated 4,829 all-time citations—and here is the number that should immediately relieve some stress: the out-of-service rate is 0.0%. Not a single one of those 4,829 citations resulted in a vehicle being placed out of service. For context, the all-FMCSR average OOS rate across all codes is 31.4%, so this violation sits dramatically below the norm. You will not be sitting on the side of the road because of this citation alone.
That said, enforcement volume is not trivial. Our records show 2,993 citations issued in just the last 12 months, and 616 citations in the last 90 days. The monthly trend data tells an interesting story: citations peaked in August 2025 at 319 in a single month, ran consistently above 200 through the winter, and hit 287 in March 2026. This is an actively enforced code that inspectors are clearly prioritizing during roadside stops.
By citation volume, 393.11B-CSLRR ranks #347 out of 3,036 FMCSR codes in our database. That places it solidly in the top 12% of all codes by enforcement frequency—common enough that fleet managers need a systematic response, not a one-off fix.
On the CSA scoring side, this violation carries a severity weight of 3. It will appear in the Vehicle Maintenance BASIC. Because it is not OOS-eligible, it won't trigger the elevated multipliers that out-of-service events do, but it still accumulates toward your percentile score with each occurrence.
Who gets cited most
Looking at the last 180 days of our inspection records, Arizona leads all states with 362 citations and a 0.0% OOS rate. California is second at 182 citations, also at 0.0% OOS. The third-busiest state is listed in federal inspection records as "US" jurisdiction with 109 citations, followed by Kansas at 52, Florida at 46, and Utah at 45. Arizona's citation count is nearly double California's, suggesting particularly active enforcement of lighting compliance in that corridor—worth knowing if you run I-10 or I-19 routes regularly.
All ten states in our top-cited list share the same 0.0% OOS rate, so there is no meaningful variation in that metric across jurisdictions. The differences are purely in enforcement volume, not in outcome severity.
Our data shows fleets such as DANIEL ERNESTO PENA COTA (USDOT 1647639) with 47 all-time citations and ALFONSO GRIJALVA GRACIA (USDOT 988857) with 30 citations appearing at the top of the carrier list. High citation counts at the carrier level typically indicate repeated exposure on specific routes or vehicle types rather than any single egregious incident.
How severe is this compared to similar codes
To calibrate how serious 393.11B-CSLRR is relative to its neighbors in the Vehicle Maintenance category, consider three peer codes from our database.
393.9(a) — Inoperable required lamps has 660,737 all-time citations and a 15.4% OOS rate. That's a code in the same lighting family but with dramatically higher enforcement volume and an OOS rate that means roughly one in seven drivers who receive it gets parked. Your 0.0% OOS rate on 393.11B-CSLRR is a significantly better outcome.
396.3(a)(1) — Inspection, repair, and maintenance (general) carries 236,919 citations and a 45.3% OOS rate—the highest of the peer group shown here. Nearly half of all citations under that code end with the vehicle out of service. This illustrates just how wide the OOS spectrum is within Vehicle Maintenance alone.
396.17C-PI — No proof of periodic inspection has 212,081 citations and a 0.0% OOS rate, making it the closest behavioral analog to 393.11B-CSLRR in terms of outcome. Both codes generate citations frequently and never park a truck, but both accumulate CSA points that compound over time.
The takeaway: 393.11B-CSLRR won't shut you down at the scale, but it's far from rare, and its peers in the lighting family can and do result in OOS events.
How to avoid it
The co-occurrence data in our records points to exactly where your pre-trip inspection needs to get tighter. In the last 90 days, 393.11B-CSLRR appeared alongside 396.17C-PI (No proof of periodic inspection) in 140 shared inspections, and with 393.55E-B (Coupling device/towing methods defective) in 115 shared inspections. That pattern means inspectors finding a lighting violation are also finding maintenance paperwork gaps and trailer connection problems on the same truck. These aren't isolated defects—they're signals of a broader pre-trip routine that needs reinforcing.
Freightliner units account for 1,232 all-time citations under this code, more than double the next closest make (Kenworth at 465). Wabash National and Great Dane trailers together add another 773 citations, confirming that the reflector and lighting checks on your trailer—not just your tractor—are where violations are being found.
Here's what to do before every trip:
- Walk the full trailer perimeter, not just the rear. Side marker reflectors and conspicuity tape on the long sides of the trailer are the specific components this code targets. Confirm each reflector is present, securely mounted, and not obscured by road grime.
- Check clearance and marker lights at the roofline. On Freightliner and Kenworth tractors, the amber marker lamps along the top of the cab are common failure points, especially after vibration on rough roads.
- Confirm your periodic inspection documentation is in the cab. The 140 co-occurring 396.17C-PI citations tell you inspectors are checking paperwork immediately after flagging a lighting issue. Have your annual inspection report accessible.
- Inspect the trailer kingpin area and coupling hardware during the same walk-around. With 115 co-occurring 393.55E-B citations, coupling defects are found in the same inspections. A complete pre-trip catches both.
- Carry spare marker lamps and reflective tape. If you discover a missing or damaged reflector during your pre-trip, replacing it before you leave is faster than dealing with a citation and the CSA points that follow.