06/07/2002
Daytime Running Lights (DRLs) have become a common feature on modern vehicles, designed to enhance visibility and safety on the roads. However, their role in the annual MOT test can often lead to confusion and, as some motorists have discovered, even unexpected failures. If your car, like the 2015 Kia Cee'd mentioned, has failed its MOT solely on its DRLs, you're not alone in questioning whether this is correct. The rules surrounding DRLs and the MOT have evolved, leading to a nuanced understanding that every UK driver should be aware of to avoid unnecessary stress and retests.
Understanding Daytime Running Lights (DRLs)
Daytime Running Lights are low-energy light sources positioned at the front of your vehicle. Their primary purpose is straightforward: to make your car more conspicuous to other road users, pedestrians, and cyclists during daylight hours. Unlike headlights, DRLs are not designed to illuminate the road ahead but rather to ensure your presence is clearly noted, especially in conditions where ambient light might make a vehicle harder to spot.
Typically, DRLs are engineered to switch on automatically when the engine is started. They are bright enough for daytime visibility but are too intense for night-time use, which is why they automatically dim or turn off when your headlights are activated. In some designs, DRLs might be integrated with front position lamps (sidelights), reducing their intensity when headlights are on. Furthermore, if DRLs are positioned close to indicators, they often temporarily switch off on the side where the indicator is flashing, preventing confusion for other drivers.
A Brief History of DRLs in the UK and Europe
The concept of always-on lighting for improved road safety isn't new. Volvo, with its 240 model in 1984, was an early adopter of DRLs in the UK. This move, while innovative, initially caused some bewilderment among drivers unfamiliar with the constant front illumination. Throughout the mid-to-late 20th century, discussions around mandatory 'dim-dip' lighting and continuous headlight use gained traction across Europe, with several countries implementing their own rules regarding daytime lighting. Countries like Sweden (since 1977), Iceland, Norway, and Denmark were early pioneers in mandating daytime use of lights.
The significant shift came in 2011 when the European Union made DRLs a legal requirement for all new types of passenger cars and small vans. This mandate was extended to new trucks and buses in August 2012. It's crucial to note that this regulation applied to *new vehicles* being manufactured and sold, not as a blanket requirement for all existing vehicles on the road to be retrofitted.
This is where much of the confusion lies, particularly for owners of vehicles registered before the most recent MOT rule changes. The question of whether a faulty DRL can lead to an MOT failure hinges critically on the vehicle's date of first registration.
The crucial date for DRL functionality in the MOT test is 1st March 2018. The Driver and Vehicle Standards Agency (DVSA) updated its MOT inspection manual around July 2019, clarifying the rules:
- For vehicles first used on or after 1st March 2018: DRLs are a mandatory inspection item. If your car was registered on or after this date, and its DRLs are missing, not working, or not illuminating correctly, this will result in a Major Defect, leading to an MOT failure. This includes situations where one DRL is out, or they are not activating as they should.
- For vehicles first used before 1st March 2018: DRLs are generally *not* part of the mandatory MOT lighting check. This means if your car, like the 2015 Kia Cee'd, was registered before this date, a non-functional DRL *should not* be the sole reason for an MOT failure. However, there are important caveats:
- Defective but not a fail: If a DRL on an older vehicle is faulty (e.g., one side is out), but the vehicle has separate, fully functional front position lamps (sidelights), it should typically not fail the MOT on the DRLs alone. It might be noted as an Advisory item, suggesting maintenance is needed.
- Construction & Use Regulations: As one expert noted, having a light on one side of the car and not the other, even if it's a DRL not explicitly checked for MOT on older cars, could potentially fall foul of broader Construction & Use regulations. This could theoretically lead to you being stopped by the police, though it's less about the MOT and more about road legality.
- Dazzle or Security Risk: Regardless of the age, any fitted light, including a DRL, must not cause dazzle to other road users, nor should it pose a security risk (e.g., hanging off, sharp edges). If a DRL is defective in a way that causes dazzle or is physically insecure, it could lead to a failure, but this would be based on a safety defect, not merely its non-operation as a DRL.
- Integrated Lights: If your DRLs are combined with other mandatory lights (like front position lamps) and the entire unit is defective, then it would fail based on the defect of the mandatory light. However, if the DRL function is separate and only the DRL part is faulty on a pre-2018 car, it should not be a fail.
Given the 2015 Kia Cee'd scenario, if the car truly failed *only* on its DRLs, and they are not integrated with other mandatory lights in a way that creates a specific safety hazard or a general lighting failure, then the MOT failure might indeed be incorrect according to DVSA guidelines for vehicles registered before 1st March 2018. It would be advisable to discuss this with the MOT test centre or seek clarification from the DVSA.
Common Reasons Your DRLs Might Not Be Working
If your DRLs aren't functioning, several issues could be at play:
- Blown Fuse: A common and relatively easy fix. Check your car's fuse box diagram for the DRL fuse and replace it if blown.
- Faulty Wiring: Damaged or corroded wiring can disrupt the electrical supply to the DRLs. This often requires professional inspection and repair.
- Dead LEDs/Bulbs: Like any light source, DRL LEDs or bulbs can burn out over time. Replacing them might be straightforward or could involve replacing the entire headlamp unit if they're integrated.
- Faulty Sensor: Many modern DRL systems rely on light sensors to determine when to activate or deactivate. A malfunctioning sensor could prevent the DRLs from coming on.
- DRL Module Failure: The control module that manages the DRL system can sometimes fail due to water ingress or internal electrical faults. This usually requires diagnostic tools to confirm and replacement of the module.
The Benefits and Considerations of DRLs
The widespread adoption of DRLs stems from their proven safety benefits. Studies, including those by the European Commission and the UK Department for Transport, have indicated a potential for significant reductions in road casualties by improving vehicle visibility. DRLs make vehicles more conspicuous, particularly in low-sun conditions, at dusk, or when emerging from shadows.
While the safety benefits are clear, there were initial concerns regarding fuel consumption and the potential for DRLs to make motorcyclists less conspicuous. Modern DRLs primarily use Light Emitting Diodes (LEDs), which consume significantly less power than traditional incandescent bulbs, thus having a minimal impact on fuel economy. Furthermore, studies suggest dedicated DRLs improve car visibility without significantly reducing the visibility of motorcyclists.
Retrofitting DRLs: What You Need to Know
While DRLs have been mandatory for new cars since 2011, there's no legal requirement to retrofit them to older vehicles. However, if you wish to add them, aftermarket kits are available. When purchasing, look for an approval mark on the lamp that includes the letters 'RL', indicating compliance with European standards. If you install them, ensure they are wired to come on automatically with the engine and switch off (or dim) when your headlights are turned on, mimicking factory-fitted systems.
DRLs and MOT: Quick Reference Table
| Vehicle First Used Date | DRL MOT Check? | Consequence of DRL Fault | Notes |
|---|---|---|---|
| Before 1st March 2018 | No (generally) | Advisory (if noted) Not a fail (unless safety hazard) | DRLs not explicitly checked. May be advisory if faulty. Can fail if they cause dazzle or are insecure. If combined with mandatory lights, defect in mandatory light causes fail. |
| On or after 1st March 2018 | Yes (Mandatory) | Major Defect (FAIL) | DRLs must be present and working correctly. Any non-functionality or imbalance (e.g., one out) results in a fail. |
Frequently Asked Questions (FAQs)
Can you turn off your daytime running lights?
For safety reasons, most modern vehicles do not allow you to manually turn off DRLs. They are designed to operate automatically. Some vehicles may have a temporary override button for specific situations, but this is rare and usually reverts to automatic operation.
Do daytime running lights come on automatically?
Yes, in the vast majority of modern vehicles, DRLs are designed to come on automatically when you start the engine. Many also feature sensors that detect decreasing ambient light, which then triggers the automatic switch to headlights while the DRLs turn off.
Are DRLs a substitute for headlights?
Absolutely not. DRLs are for daytime visibility only. They are not bright enough and do not illuminate the road sufficiently for use in low-light conditions, at night, or in adverse weather. Using DRLs instead of headlights when required can be dangerous and may lead to legal penalties for improper lighting.
What controls daytime running lights?
DRLs are typically controlled by a dedicated DRL module within the vehicle's electrical system, often located in the engine compartment or behind the dashboard. This module communicates with various sensors, such as ambient light sensors, to manage the DRLs' activation, deactivation, and dimming.
What if only one DRL is working?
If your car was first used on or after 1st March 2018, only one DRL working will result in an MOT failure (Major Defect). For older cars, while it might not be an MOT failure on its own, it could lead to an advisory and potentially fall under Construction & Use regulations for an unbalanced lighting display, which could attract police attention.
Conclusion
The world of automotive lighting, particularly concerning DRLs, can be complex, especially when it intersects with MOT regulations. The key takeaway is the 1st March 2018 cut-off date for MOT checks on DRL functionality. If your vehicle was registered before this date and failed its MOT solely on DRLs, it's worth reviewing the specific defect noted and the MOT manual to determine if the failure was correctly applied. Always consult your car's manual for details on your specific DRL system and, if in doubt, seek advice from a reputable mechanic or the DVSA directly to ensure your vehicle is compliant and safe for the road.
If you want to read more articles similar to DRLs and Your MOT: Navigating the Rules, you can visit the Maintenance category.