More than one in ten UK drivers could be in need of investing in second hand car parts in the form of replacement brake lights.
According to a new survey by TescoCars.com, more than 11 per cent of UK vehicles are missing one or more brake lights, in many cases resulting in them being un-roadworthy.
Around 3.7 million of the 34 million cars on the country's roads would fail an MOT due to faulty brake lights - roughly one in nine vehicles - while the drivers themselves could end up with a £60 fine and penalty points on their licence.
Furthermore, the number of cars with broken or missing brake lights is increasing, rising 68 per cent since 2010.
Four per cent of vehicles with faulty brake lights had no bulbs working at all, while commercial vehicles, which often spend a much bigger amount of time on the road, made up eight per cent of total brake light failures.
Rebecca Ryan, marketing manager for Tesco Cars, called the results of the survey "alarming".
"It's a major concern for road safety and a potentially fatal fault in low light conditions," she added.
She also urged drivers to regularly check that their lights are clean and functional, asking a friend or family member to assist them if necessary.
But it's not just brake lights that vehicle owners may need to replace with spare car parts - over one million vehicles (three per cent) had at least one non-functioning headlight, the study found, a surprisingly high amount given that this is a problem much easier to spot than a malfunctioning brake light.
Driving at night or in poor conditions without fully working headlights can be particularly dangerous, warned Tesco Cars, as it not only restricts the driver's view but makes the vehicle harder to spot for other motorists.