Winter is the harshest test your car faces all year. Cold weakens batteries, ice ruins visibility, salt eats at the bodywork and wet roads punish tired tyres. The good news is that nearly all of it is predictable, and therefore preventable. Every January our diary fills with breakdowns that a half-day of prep would have avoided.

The battery comes first

Cold weather is the number-one killer of car batteries, and most flat-battery call-outs happen on the first really cold mornings. A battery that was 'fine' in October can fail the moment the temperature drops, especially on short journeys that never let it fully recharge.

  • Have the battery tested before winter if it's more than three years old
  • Take the occasional longer drive to keep it properly charged
  • Check the terminals are clean and tight
  • Switch off heaters, lights and heated screens before you turn the key

Tyres and stopping distance

Tread depth is what clears water and slush from under your tyres. The legal minimum is 1.6 mm, but grip falls off well before that — many drivers fit winter or all-season tyres once temperatures regularly drop below 7°C, when standard summer tyres start to harden and lose grip.

Visibility — screenwash, wipers and lights

Short winter days mean you'll use lights, wipers and screenwash far more. Wiper rubber hardens and splits over a hot summer, so blades that worked in August will smear in December.

  • Top up the washer bottle with a proper winter screenwash that won't freeze
  • Replace wipers that smear, judder or skip across the glass
  • Check every exterior light works — you'll be driving in the dark far more
  • Keep a de-icer and scraper in the car; never drive off peering through a small clear patch

Under the bonnet

Antifreeze does two jobs: it stops the coolant freezing and raises its boiling point. A weak mix can freeze and crack an engine block — one of the most expensive winter repairs there is. Have the strength checked at your service. Keep the fuel tank topped up too; condensation in a near-empty tank is more of a problem in the cold.

After the salt

Grit and road salt accelerate rust, especially around the underbody, sills and brake lines. A regular winter wash that rinses the underside is cheap insurance against the slow corrosion that shortens a car's life and shows up as advisories at MOT time.