Avoiding DOT Lighting Violations

Avoiding DOT lighting violations isn’t complicated. In most cases, it only takes a few minutes each week to check your truck and stay in compliance with the FMCSA lighting regulations. Truck drivers should always strive to be in full compliance, because lighting issues trigger nearly 70% of all roadside inspections.

We often call them “gateway violations” — once an officer spots a bad light, it becomes an easy gateway to a deeper inspection of the driver, vehicle, and paperwork. And year after year, lighting problems remain one of the most common DOT violations truck drivers receive.

A truck or trailer with a light out is like an open invitation to be pulled over and inspected!

Keeping your lights in good working order will not only will it save you time and money, but will also allow you to focus on what really matters: driving safely! Helping to maintain good CSA scores doesn’t hurt either, of course!

Check out our short video to learn more about the DOT lighting regulations and how to avoid these critical DOT violations:

Why Avoid Lighting Violations?

DOT Lighting violations (DOT lighting requirements for trucks are covered under FMCSA 393.11 ) are a leading cause of roadside inspections.

Bad roadside inspections lead to high CSA BASIC scores for your fleet and violation points on a driver CSA score.

High CSA BASIC scores lead to compliance reveiws (DOT audit).

A DOT audit can lead to a conditional safety rating.

A Conditional Safety Rating leads to fewer loads, less profit and higher truck insurance premiums!

CSA Points for Common DOT Lighting Violations

Here are the CSA Severity Points for the most common violations of the DOT lighting regulations:

CFR Section	Violation (plain-language description)	CSA Severity Points*
393.9	Inoperable required clearance or identification lamp	2
393.9H	Inoperable headlamps	6
393.9T	Inoperable tail lamp	6
393.9TS	Inoperative turn signal	6
393.9BRKLAMP3	Inoperative brake lamps	6
393.11	No or defective required lamps/lighting devices or reflective material	3
393.11A1-LCHL	Lamps improper color, height, or location	6
393.19	Inoperative or defective hazard warning lamps	6
393.24(a)	Non-compliance with headlamp requirements	6
393.25(b)	Required lamps not visible as required	6
393.25(f)	Stop lamp violations	6
393.26	Missing or improper reflectors as required	3

As you can see in the chart, violations involving the main lighting systems—headlamps, brake lights, and turn signals—carry much higher CSA points. They’re roughly twice as severe as the violations of the DOT lighting regulations for reflective tape/sheeting and about three times higher than violations for clearance or identification lights. This clearly shows that FMCSA treats these critical lighting violations far more seriously.

Setting The Stage

This guide provides some tips to help drivers avoid getting pulled over for an inspection by local law enforcement officers, the DOT or state police. Check out the DOT’s Lighting and Reflective Sheeting guide that helps explain what’s required here!

As part of our trucking compliance services, we can complete a quick “Virtual Lighting Inspection” for each of your trucks (and trailers) as needed in order to ensure compliance.

DOT light regulations require keeping the following lights and lamps in proper working order:

• Headlights
• Brake lights
• Turn signals
• Other lights (clearance and Identification lamps)
• Reflective Sheeting

If an officer finds out you have broken any DOT lighting regulations during the inspection process, they may issue a warning or cite you with a violation for doing so.

DOT Truck Lighting Requirements: Front of Truck

Here are the DOT truck lighting requirements:

Device / Function	Requirement
Headlamps	Two white headlamps on the front, placed symmetrically at equal height, 22–54 inches above the roadway.
Front Turn Signals	Two amber lamps, one on each side, between 15–83 inches above the roadway.
Front Identification Lamps	Three amber lamps centered at the top of the cab to indicate vehicle width and height.
Front Clearance Lamps	Two amber lamps, one on each side near the top corners, showing the full width of the vehicle.

DOT Truck Lighting Requirements: Rear of Truck

Here are the DOT lighting requirements for the rear of a semi truck:

Device / Function	Requirement
Tail Lamps*	Two red lamps, one on each side, 15–72 inches above the road surface.
Stop Lamps (Brake Lights)*	Two red lamps, same height and position as tail lamps, activated by brake pedal.
Rear Turn Signals*	Two amber or red lamps, one on each side, 15–83 inches above the roadway.
Rear Clearance Lamps (Straight Truck Only)	Two red lamps, one on each upper rear corner, to indicate overall width.
Rear Identification Lamps (Straight Truck Only)	Three red lamps, centered horizontally near the top of the vehicle.
License Plate Lamp	One white lamp to illuminate the license plate from the top or sides.
Backup Lamp	1 or 2 white lamps on the rear of the unit, no height requirement.
Rear Conspicuity Tape	Red-and-white reflective sheeting covering top of mud-flaps. White Rear Upper Body Marking consisting of 2 12 inch strips forming an upside down “L” shape at the top left and right of a semi truck power unit.

* Note: Lamps and reflectors may be combined as permitted by § 393.22 and S5.4 of 49 CFR 571.108, Equipment combinations.

DOT Trailer Lighting Requirements: Rear of Semi-Trailer

Here are the rear DOT trailer lighting requirements:

Device / Function	Requirement
Tail Lamps	Two red lamps, one on each side at equal height, visible from the rear.
Stop Lamps (Brake Lights)	Two red lamps that activate when brakes are applied.
Rear Turn Signals	Two amber or red lamps, one on each side, visible from the rear.
Rear Identification Lamps	Three red lamps centered near the top rear of the trailer.
Rear Clearance Lamps	Two red lamps, one on each upper rear corner, marking overall width.
Rear Conspicuity Tape	Red-and-white reflective sheeting covering at least 50% of trailer width along the lower rear.

DOT Trailer Lighting Requirements: Sides/Remainder of Semi-Trailer

Here are the side and front DOT lighting requirements for trailers:

Device / Function	Requirement
Side Marker Lamps (Front Side)	Amber lamp near the front corner, steady-burning, 15 inches or higher above the roadway.
Side Marker Lamps (Rear Side)	Red lamp near the rear corner, steady-burning, 15–60 inches above the roadway.
Intermediate Side Marker Lamps	Amber lamps or reflectors placed midway along each side on trailers 30 feet or longer.
Side Conspicuity Tape	Continuous red-and-white reflective sheeting along at least 50% of each side, as low as practicable.

Preventing DOT Lighting Violations

In order to avoid lighting violations during a DOT vehicle maintenance inspection, drivers should adhere to the following guidelines:

Avoiding DOT Lighting Violations: General Guidelines

A clean, well-maintained lighting system is your first line of defense. Dirt, road grime, and debris can block lenses and reduce visibility, especially at night or in bad weather. Make it a habit to:

1. Keep all lamps, lenses, and reflective devices clean and free of debris.
2. Look for cracked, broken, or missing lenses and replace them promptly.
3. Check wiring and connections for damage, corrosion, or loose fittings.

Avoiding DOT Lighting Violations: Headlamps and Other Major Lights

Your major lights (headlamps, tail lamps, and turn signals) are some of the first DOT lighting requirements an inspector will check—and they carry higher CSA violation weights when they’re not working.

Drivers should:

1. Use headlights whenever driving at night or in low-visibility conditions.
2. Understand that daytime running lights (DRLs) may be turned off between sunrise and sunset, but make sure your main headlamps are used when required by state law or conditions.
3. Ensure license plate lamps are unobstructed by dirt, covers, or stickers and are visible from at least 50 feet when illuminated.
4. Inspect all primary lighting equipment during every pre-trip inspection, and pay extra attention during rain, snow, fog, or other adverse weather.
5. Report and repair any inoperative or damaged DOT-required lamps immediately.

DOT headlight regulations require that all required headlights be in proper working order and visible from at least 500 feet. A simple pre-trip light check helps confirm that other drivers can clearly see your truck from the front, rear, and both sides.

If a DOT officer finds a problem with your major lights (headlamps, tail lamps, or turn signals) during an inspection, you will typically be required to correct the defect before being allowed to continue down the road.

DOT-Compliant LED Headlamps

More fleets are switching to LED headlamps for better visibility and longer life, and that’s perfectly fine as long as they’re truly DOT approved LED headlights. Look for complete headlamp assemblies that are marked “DOT” on the lens and designed for LED from the factory or as a full replacement – not cheap “bulb-only” LED conversion kits stuck into old halogen housings, which can create glare and push you out of compliance.

Treat LED headlamps just like any other required light: make sure they’re aimed correctly, stay clear and undamaged, and are checked during every pre-trip and post-trip inspection. If an LED module burns out, fills with moisture, or gets too dim, it still needs to be repaired or replaced before you hit the road.

Avoiding Lighting Violations: Other Lights and Reflective Sheeting

While major lights draw most of the attention, many violations of the DOT lighting requirements come from smaller lamps and reflective materials. Common issues include:

1. Missing, damaged, or inadequate reflective sheeting.
2. Brake light outages or dim brake lamps.
3. Driving with only parking lights on instead of required headlamps when the truck is in motion.

Remember, headlights are not the only DOT-required lights that officers will inspect. On the rear of your truck and trailer, red taillights and red stoplights are also required and must be visible from at least 500 feet.

In 2026, the FMCSA will be splitting the Vehicle Maintenance CSA BASIC score into 2 parts: VM: Driver Observed and VM. Learn more about these and other upcoming changes to the FMCSA CSA program here!

You can quickly verify that your brake lights are working by having someone watch the rear of the vehicle while you press the brake pedal. If they do not illuminate, one or more bulbs, fuses, or circuits may need to be repaired or replaced.

Trailer marker lamps, identification lamps, and DOT clearance lamps are also critical. These small lamps help define the size and shape of your vehicle in the dark. A DOT officer can easily verify whether trailer marker lamps work during a Level 1 or Level 2 inspection, so you should:

1. Confirm that all marker, clearance, and identification lamps are present, clean, and working.
2. Make sure these lamps come on with your parking lights or headlamps.
3. Replace burned-out bulbs or repair faulty wiring as soon as defects are found.

Remember that all of your lighting systems, as well as your compliance with any applicable DOT window tint regulations, will be reviewed during your required annual DOT inspection. Any lighting defects noted there can also create problems during roadside inspections if they are not addressed.

A simple pre-trip light check ensures all required lamps work properly so other drivers can see them clearly from both sides, the front and the rear.

Putting It All Together

Make lighting a standard part of every pre-trip and post-trip inspection. Walk around your vehicle and trailer, check every required lamp (front, rear, and sides), and verify that your lights and reflective sheeting are visible and functioning as intended.

When all required DOT lighting is working properly and kept in good condition, there is far less for an inspector to write up—and far more safety for you, your cargo, and everyone else on the road.

FAQ: Avoiding DOT Lighting Violations on Commercial Motor Vehicles (CMVs)

What lights are required on a CMV?

You must have working headlamps, tail/stop lamps, turn signals, license-plate light, clearance/side-marker lamps, ID lamps (for wide vehicles), reflectors, and hazard flashers. All required lights must be present, functional, correctly colored, and properly positioned.

What triggers the most lighting violations?

The big three are: inoperative lamps (burnt bulbs, bad LEDs), improper color (white/blue where amber/red is required), and obscured or missing lights/reflectors due to damage, dirt, or cargo.

Do wide vehicles need three identification (ID) lamps?

Yes. CMVs 80 inches or wider require three amber ID lamps on the front and three red ID lamps on the rear, centered and evenly spaced.

Are smoked or tinted lenses allowed?

Avoid them. Dark lenses reduce effective light output and often lead to “improper color/insufficient visibility” violations, especially at night or in bad weather.

How do officers check my lights during inspections?

They verify presence, color, location, and operation (on/off, signal, brake application). Many will also look for cracked lenses, moisture intrusion, loose wiring, and secure mounting.

Which lighting defects can place me out of service?

Critical lamps—headlamps (at night), stop lamps, and turn signals—can be OOS if inoperative. A single side-marker outage is usually not OOS but still a violation.

Do trailers and dollies have special requirements?

Yes. Trailers must have functional tail/stop/turn lamps, side-marker/clearance lamps, reflectors, a license-plate light, and required conspicuity (reflective) material. Converter dollies need proper lamps/reflectors when operated.

What about conspicuity (reflective tape)?

Trailers require red/white conspicuity on the sides and rear. Keep it complete, clean, and unpeeled. Missing or damaged sections are common violations. (Don’t forget about the required reflective sheeting on your mud flaps).

Are LED upgrades worth it?

Often, yes. Quality LEDs reduce bulb failures and draw less power, but they must meet color/brightness standards and be installed with proper connectors, grounds, and resistors (if needed) to prevent hyper-flash.

Why do my lights work intermittently?

Corroded grounds, damaged pigtails, loose connectors, chafed wiring, and water-filled housings are typical culprits. Use sealed connectors, strain relief, grommets, loom, and dielectric grease.

How can drivers prevent lighting violations on the road?

Do a true walk-around at start of day, use reflective surfaces or a wall to check brake/turn/marker function solo, and re-check at fuel stops—especially after rain or rough roads.

What maintenance practices cut violations fleet-wide?

Standardize LED kits, stock spare fuses/bulbs/pigtails, clean lenses and conspicuity during washes, add quick-test harnesses at shops, and log findings in DVIRs with fast repair turnarounds.

Do aftermarket light bars or strobes help or hurt?

Extra amber warning lights can improve visibility at job sites, but non-compliant colors or placements may draw citations. Never substitute add-ons for required lamps.

What documentation should I keep?

Keep DVIRs, repair orders, parts receipts, and—if applicable—spec sheets showing lamps meet required color/brightness standards. Clean, recent documentation supports your compliance story during audits.

What’s the quickest pre-trip checklist for lights?

Power on headlamps and markers, test four-ways, left/right turn signals, brake lights, license-plate light, and tractor-trailer connections. Confirm ID lamps, clearance/side-markers, reflectors, and conspicuity are present, visible, and secure.

If you’re not following the DOT lighting regulations then YOU’RE putting yourself at risk! Let us take care of ALL your DOT needs. We make it easy! Avoid fines, penalties & stay compliant with our affordable trucking compliance services. Call or go online now. 1-855-211-5550 or www.MySafetyManager.com.

Regulatory References

Key federal regulations and FMCSA guidance governing commercial motor vehicle lighting, reflectors, inspections, and CSA scoring.

• 49 CFR Part 393 – Parts and Accessories Necessary for Safe Operation
• 49 CFR §393.9 – Lamps operable; prohibition of obstructions of lamps and reflectors
• 49 CFR §393.11 – Lamps and reflective devices
• 49 CFR §393.24 – Requirements for head lamps, auxiliary driving lamps and front fog lamps
• 49 CFR §393.25 – Requirements for lamps other than head lamps
• 49 CFR §393.26 – Requirements for reflectors
• 49 CFR Part 396 – Inspection, Repair, and Maintenance
• 49 CFR §396.17 – Periodic inspection
• FMCSA CSA Program – Compliance, Safety, Accountability (Vehicle Maintenance BASIC)