Vehicle maintenance, safety and security

Part of: The Highway Code, The Highway Code Annexes

Take special care that lights, brakes, steering, exhaust system, seat belts, demisters, wipers and washers are all working.

Vehicle maintenance

  • lights, indicators, reflectors and number plates must be kept clean and clear
  • windscreen and windows must be kept clean and free from obstructions to vision
  • lights must be properly adjusted to prevent dazzling other road users - extra attention needs to be paid to this if the vehicle is heavily loaded
  • exhaust emissions must not exceed prescribed levels
  • ensure your seat, seat belt, head restraint and mirrors are adjusted correctly before you drive
  • ensure that items of luggage are securely stowed

Laws RVLR regs 26 & 30, & CUR regs 35 & 74

Warning displays. Make sure that you understand the meaning of all warning displays on the vehicle instrument panel. Do not ignore warning signs; they could indicate a dangerous fault developing.

  • when you turn the ignition key, warning lights will be illuminated but will go out when the engine starts (except the handbrake warning light), if they do not, or if they come on while you are driving, stop and investigate the problem, as there could be a serious fault
  • if the charge warning light comes on while you are driving, it may mean that the battery isn’t charging - this must also be checked as soon as possible to avoid loss of power to lights and other electrical systems

Window tints. You must not use a vehicle with excessively dark tinting fitted to the windscreen, or to the glass in any front window to either side of the driver - window tinting applied during manufacture complies with the visual light transmittance (VLT) standards. There are no VLT limits for rear windscreens or rear passenger windows.

Laws RTO 1995 Art 58, CUR reg 37 & CU(A)R 2005

Tyres. Tyres must be correctly inflated to the vehicle manufacturer’s specification for the load being carried. Always refer to the vehicle’s handbook or data. Tyres should also be free from certain cuts or other defects.

Cars, light vans and light trailers must have a tread depth of at least 1.6mm across the central three-quarters of the breadth of the tread and around the entire circumference.

Motorcycles, large vehicles and passenger-carrying vehicles must have a tread depth of at least 1mm across three-quarters of the breadth of the tread and in a continuous band around the entire circumference.

Mopeds should have visible tread.

Be aware that some vehicle defects can attract penalty points.

Law CUR reg 32

If a tyre bursts while you are driving, try to keep control of your vehicle.  Grip the steering wheel firmly and allow the vehicle to roll to a stop at the side of the road.

If you have a flat tyre, stop as soon as it is safe to do so. Only change the tyre if you can do so without putting yourself or others at risk – otherwise call a breakdown service.

Tyre pressures. Check weekly. Do this before your journey, when tyres are cold. Warm or hot tyres may give a misleading reading.

Your brakes and steering will be adversely affected by under-inflated or over-inflated tyres. Excessive or uneven tyre wear may be caused by faults in the braking or suspensions systems, or wheels which are out of alignment. Have these faults corrected as soon as possible.

Spacesaver tyres, often referred to as ‘get you home tyres’, are speed or distance rated. Advice on their use can be found on the tyre or in the vehicle handbook.

Run flat tyres, which should only be used in conjunction with a tyre pressure monitoring system, enable vehicles to continue at reduced speeds for a limited distance following a puncture. Advice on their use can be found in the vehicle handbook.

Fluid levels. Check the fluid levels in your vehicle at least weekly. Low brake fluid may result in brake failure and a collision. Make sure you recognise the low fluid warning lights if your vehicle has them fitted.

Before winter. Ensure that the battery is well maintained and that there are appropriate anti-freeze agents in your radiator and windscreen bottle.

Other problems. If your vehicle:

  • pulls to one side when braking, it is most likely to be a brake fault or incorrectly inflated tyres - consult a garage or mechanic immediately
  • continues to bounce after pushing down on the front or rear, its shock absorbers are worn (worn shock absorbers can seriously affect the operation of a vehicle and should be replaced)
  • smells of anything unusual such as burning rubber, petrol or an electrical fault; investigate immediately - do not risk a fire

Overheated engines or fire. Most engines are water-cooled. If your engine overheats you should wait until it has cooled naturally. Only then remove the coolant filler cap and add water or other coolant.

If your vehicle catches fire, get the occupants out of the vehicle quickly and to a safe place. Do not attempt to extinguish a fire in the engine compartment, as opening the bonnet will make the fire flare. Call the Fire and Rescue Service.

Petrol stations/fuel tank/fuel leaks. Ensure that, when filling up your vehicle's tank or any fuel cans you are carrying, you do not spill fuel on the forecourt. Any spilled fuel should be immediately reported to the petrol station attendant.

Diesel spillage is dangerous to other road users, particularly motorcyclists, as it will significantly reduce the level of grip between the tyres and the road surface. Double-check for fuel leaks and make sure that:

  • you do not overfill your fuel tank
  • the fuel cap is fastened securely
  • the seal in the cap is not torn, perished or missing
  • there is no visual damage to the cap or the fuel tank

Emergency fuel caps, if fitted, should form a good seal.

Never smoke, or use a mobile phone, on the forecourt of petrol stations as these are major fire risks and could cause an explosion.

Vehicle security

When you leave your vehicle you should:

  • remove the ignition key and engage the steering lock
  • lock the car, even if you only leave it for a few minutes
  • close the windows completely
  • never leave children or pets in an unventilated car
  • take all contents with you, or lock them in the boot - remember a potential thief might assume a carrier bag contains valuables
  • never leave vehicle documents in the car

For extra security fit an anti-theft device such as an alarm or immobiliser. If you are buying a new car it is a good idea to check the level of built-in security features. Consider having your registration number etched on all your car windows. This is a cheap and effective deterrent to professional thieves.

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