Winter Motoring Checklist: 12 Checks to Make Before the First Frost

The first frost doesn't announce itself. You find it one morning as a pale film across the windscreen, or hear it in a starter motor that turns over a fraction slower than it did last week. By then, most of the choices that decide whether the car starts and stops well this winter have already been made. A battery that's been lazy since August, tyres down to three millimetres, screenwash topped up with water back in July — none of it matters until the temperature drops, and then all of it matters at once.

The good news is that the whole checklist below takes an afternoon, needs nothing more exotic than a tyre pressure gauge and a torch, and costs far less than a recovery truck on a dark Tuesday in January. Work through it before the first hard frost and you'll spend the winter driving rather than waiting.

Battery: the usual suspect

Cold is unkind to batteries. It thickens the engine oil, slows the chemical reaction inside the cells, and asks more cranking current from a battery that has less to give. Something that feels perfectly healthy in October can be defeated by a genuine frost.

Start by looking. Terminals should be clean, tight and free of the white, furry corrosion that creeps in over time; a stiff brush and a smear of petroleum jelly on the posts will keep it away. Check that the clamp holds the battery firmly, because vibration kills plates. If you can read the date code and the battery is more than four or five years old, have it load-tested at a garage rather than waiting to find out the hard way. Slow cranking when cold, lights that dim at idle and a faint flicker of the dash lights when you turn the key are all worth taking seriously.

If you mostly do short trips — school run, shops, home — the alternator rarely gets long enough to fully recharge the battery. A trickle charger used overnight once a fortnight makes a real difference.

Tyres: tread, pressure and compound

Tyres are the only thing connecting you to the road, and cold weather changes how they behave. Rubber hardens as temperatures fall, so a summer tyre that grips well at 20°C feels wooden at 3°C. That is why winter or all-season tyres make sense in many climates, even where snow is rare.

Check three things:

• Tread depth. The legal minimum in the UK is 1.6mm, but for cold, wet roads 3mm is a far more sensible floor. Measure across the width and at several points around the tyre — worn inner shoulders are easy to miss.
• Pressure. Check when the tyres are cold, using the figures in the handbook or on the door pillar rather than the maximum moulded into the sidewall. Pressure falls with temperature, so a tyre that was right in September can be noticeably soft now, and soft tyres wear faster and grip worse.
• Condition. Look for cuts, bulges and cracking in the sidewalls, and make sure the spare or the repair kit is actually usable.

If you fit winter wheels, do it as a set of four; mixing compounds front to rear upsets the balance of the car. And if your car has a tyre pressure warning system, learn how to reset it before a cold morning forces you to.

Coolant, screenwash and oil

Engine coolant is usually a 50/50 mix of antifreeze and water, and that mix is what stops the block cracking on a hard freeze. If you have been topping up with plain water, the concentration drifts and the protection drops. A garage can check it in seconds with a hydrometer. If the level is low, top up with the correct pre-mixed coolant rather than water, and only check the level when the engine is cold.

Screenwash is the one people forget. Summer-diluted fluid freezes in the pipe or the bottle, leaves you blind in the spray thrown up by a salted road, and in bad cases cracks the reservoir. Use a winter-strength mix and keep a spare bottle in the boot.

While you're under the bonnet, check the oil level and note the grade. If your handbook allows a marginally thinner oil for cold starts, a winter oil change is cheap insurance. Squeeze the hoses too: brittle, hard-feeling rubber and cracking at the ends are warnings worth acting on before a split leaves you stranded.

Lights: dark mornings, darker evenings

Winter means most of your driving happens in the gloom, so a failed bulb matters far more now than it would in June. Get someone to help, or back up to a wall or a shop window, and work through everything: headlights on dipped and main beam, sidelights, indicators front and rear, brake lights, reverse lights, fog lights and number plate illumination. Clean the lenses while you're at it, because a film of road grime can cut output noticeably and dirty lights make you look further away than you are.

If you regularly carry a heavy load or tow, check the headlight aim. And leave the fog lights off unless visibility genuinely demands them — they dazzle other drivers and can mask your brake lights from behind.

Wipers, glass and doors

Wiper blades are consumable and cost little. If yours smear, chatter or leave a stripe across your view, replace them now. Before a frost, lifting the blades clear of the screen stops them freezing to the glass and tearing when you switch them on.

Keep a proper scraper and de-icer in the car. A credit card will scratch the screen, and pouring hot water on frozen glass can crack it; use cold or lukewarm water, or better, a de-icing spray and a few minutes of patience. A rubber treatment on the door seals helps stop them freezing shut, and a spray of silicone or graphite does the same for the lock barrels.

Build an emergency kit

You probably won't need it. The point is that when you do, you'll need it badly, and gathering it takes ten minutes.

• Ice scraper, de-icer and a soft brush
• Torch with fresh batteries, plus a spare set
• Jump leads or a lithium jump pack
• Warm blanket, hat, gloves and a spare jacket
• High-visibility vest for each occupant
• Warning triangle and a reflective breakdown sign
• Phone charger or power bank kept permanently in the car
• Bottled water and snacks that survive the cold
• Small shovel, plus grit, sand or cat litter for traction
• Basic first aid kit and any personal medication

Keep the fuel tank at least half full through winter. It reduces condensation in the tank and means you can keep the heater running for warmth if you're stuck waiting for help.

Adjust your habits, not just the car

Cold changes how a car responds, so change how you drive it. Leave longer gaps, brake earlier and more gently, and steer with smooth inputs — the grip you had in September is no longer there, particularly on bridges, in shaded dips and on untreated side roads. Set off gently rather than revving a cold engine, and keep the revs low until the temperature gauge begins to move.

Inside the car, rubber mats and a dry interior help stop condensation fogging the glass. Check the heater and demister work properly now, and remember that air conditioning can clear a misted screen faster than heat alone. Never leave the engine running with the car unattended to defrost it: it is an easy target for thieves, insurers take a dim view of it, and in some places it is an offence on a public road.

The afternoon that pays for itself

Pick a dry, reasonably mild afternoon and work through the list in order, noting anything that needs a garage. Book those jobs early, because tyre fitters and battery suppliers get busy the week the first cold snap lands.

Then keep it simple for the rest of the season: a weekly walk around the car to check the lights and tyres, screenwash topped up, and a monthly glance at pressures and fluid levels. Write your correct tyre pressures on a card and keep it in the glovebox, so you never have to guess on a freezing forecourt. Fifteen minutes here and there, and winter stops being something that happens to your car.

Photo: bluebudgie / Pixabay