A fleet gets winter-ready in one visit by checking five things on every car — salt exposure, screenwash, lights, tyres and battery terminals — as part of a recorded 20-point check done while the car is valeted on site. Nothing is left to a driver’s memory, and the fleet manager ends the day with a dated record per car.
What should a winter fleet check cover?
Five items, each of which fails more often in cold, wet and dark conditions:
- Salt — road grit and brine corrode paintwork and underbody metal; unprotected panels and exposed fixings deteriorate all season.
- Screenwash — summer dilutions freeze in the bottle and lines; winter-strength fluid keeps the system working below freezing.
- Lights — shorter days move more driving into darkness; one failed bulb is a defect and a safety risk.
- Tyres — tread depth and sidewall condition decide grip on wet and icy roads; the legal minimum tread for cars is 1.6 mm.
- Battery terminals — corroded or loose terminals cause slow cranking and failed starts, and cold weather is when they show.
Why is road salt the slowest winter damage?
Because it keeps working long after the car has been driven. Road salt and brine sit on paintwork and in wheel arches, where moisture and spray keep them working long after the gritters have passed. Brine is the faster-acting of the two: it is applied wet and gets into seams, fixings and underbody cavities almost immediately, where it starts the corrosion process at a rate that ordinary winter rain does not. The underside takes the worst of it — exposed metal, brackets, brake lines and suspension fixings — and the damage appears as corrosion months later, by which point the salt is long gone. Regular valeting through the winter takes salt off the paintwork, arches and wheels before it dries in place, and a PureShield layer makes the paint harder for salt-laden water to cling to. The underside is beyond what a valet reaches, so salt exposure and any corrosion spotted around sills and arches should be flagged to the servicing garage. How salt attacks a car, and what protects it, is covered in protecting fleet cars from road salt.
Why does screenwash need the winter formulation?
Because a summer mix can freeze. A summer mix left in the bottle can freeze at the nozzle, leaving a driver blind at the exact moment road spray is worst. The fix is winter-strength fluid topped up in every vehicle before temperatures drop. It is the cheapest item on the checklist and the one most likely to be skipped, because no driver notices screenwash until the washer runs dry or freezes. Washer fluid level is one of the 20 points, so a single on-site pass checks it across the fleet in one go, rather than waiting for individual drivers to flag it — or not.
Why do lights matter more in winter?
Because more of the working day is driven in the dark. Through autumn and winter, both ends of the working day happen in darkness or low light. A failed bulb is not a cosmetic fault; it is a defect that takes a vehicle off the road and puts the driver at risk on unlit routes. Checking dipped beam, main beam, indicators, brake lights and rear lamps on every vehicle takes minutes at a depot, but only if someone stands there and does it systematically. A fleet that waits for a driver to report a light out has already missed the point: the driver often cannot see their own failed tail lamp.
How does tyre condition affect winter grip?
Tyres near the legal limit clear less water and grip less on cold, wet roads. Tread depth and sidewall condition matter more in the wet and cold than at any other point in the year. The legal minimum tread depth for cars is 1.6 mm across the central three-quarters of the tread, but that is a floor rather than a target — tyres near the limit clear less water and give less grip on cold, wet roads, which is why tyre safety organisations recommend replacing at 3 mm rather than waiting for the legal minimum. A systematic check across the fleet flags tyres that are legal but worn, and the same pass catches sidewall damage that a driver would not notice until a blowout. Because tyres wear unevenly, a single visual pass at the start of winter is worth more than a year of occasional glances.
Why do battery terminals fail in cold weather?
Cold starts demand the most from a battery, and corroded or loose terminals are where that demand meets its weakest point. The white corrosion that forms on the posts adds resistance and prevents a clean start, and a loose clamp does the same. Battery terminals are one of the 20 points, so corrosion or a loose clamp is flagged before the first frozen morning, while cleaning and tightening them is still a short job. This is exactly the kind of item a driver does not check until it fails, which is why it belongs on a scheduled pass rather than a breakdown report.
How does the 20-point check fit into one on-site pass?
It runs alongside the valet. Each of the items above is part of the 20-point Vehicle Health Check, done in a single on-site pass where the cars are parked. The valet and the inspection happen together: the vehicle is cleaned, the winter items are checked, and the results are recorded, so the fleet manager ends the visit with a condition record for every vehicle rather than a pile of ad-hoc driver reports. The value of doing it in one pass is that the check rides on a task that already happens — the clean — instead of requiring a separate workshop visit, a separate booking, and a separate day of downtime.
Why does one visit beat a rolling programme of driver checks?
Because it is complete and consistent. A rolling programme of driver checks sounds fine on paper and drifts in practice. Drivers check what they remember, record what is convenient, and the fleet manager assembles the picture from whatever comes back. A single on-site pass inverts that: every vehicle gets the same five items plus the full 20-point check, in the same order, on the same day, and the record comes back in one format. For a fleet manager with duty-of-care obligations, that consistency is the point — a winter readiness check is only useful if it is complete and repeatable.
What should a winter check record?
Each car’s tyre depths, battery terminal condition, light check and washer fluid level, in one format against one date. A winter readiness pass is only as useful as the record it leaves. Each vehicle needs its tyre depths noted, its battery terminal condition marked, its light check signed off, and its washer fluid level logged — in one format, against one date, so a fleet manager can show what was done and when. For fleets that answer to duty-of-care obligations, that record is the difference between a check that happened and a check that can be proven. Doing the clean and the check together means the record is generated as a by-product of a task that was going to happen anyway, not bolted on as a separate administrative exercise.
For fleets running across the Surrey and south-west London area, the same waterless system operates at mobile car valeting in Esher and car valeting in Kingston upon Thames, so the on-site model works whether the fleet is at one site or several. Fleet programmes are set out on our Corporate fleet services page.
Fleet managers can scope a winter readiness pass across their cars through a Fleet Readiness Audit.