British drivers prepare for winter and ignore summer, which is the wrong way round in one important respect: heat is harder on a car than cold. Batteries degrade faster in heat than in frost, tyre failures cluster on hot motorways, and the interior takes UV damage that is permanent.
There is also a safety issue that matters more than anything mechanical, covered below.
Never Leave Anyone in a Parked Car
This comes first because the consequences are the most serious in the article. The interior of a parked car heats rapidly in sun, reaching temperatures far above the outside air within minutes, and opening a window makes little difference.
Never leave a child or an animal in a parked vehicle, even briefly, even in shade, even with windows open. Children are affected considerably faster than adults, and dogs cannot cool themselves effectively.
If you see an animal in distress in a hot car, call 999. If you see a child, call 999. This is treated as an emergency.
Tyres in Heat
- Check pressures cold, before driving. Heat raises pressure, so a warm reading looks higher than the true cold figure and you may end up underinflated.
- Underinflation plus heat plus motorway speed is the classic blowout combination. Flexing sidewalls generate heat, and a hot underinflated tyre can fail suddenly.
- Adjust for load before a holiday trip, using the laden figures in the handbook.
- Inspect sidewalls for cracking, which UV and heat accelerate, particularly on older tyres or a vehicle that stands outside.
- Check the spare, which is easy to forget and commonly needed in summer.
- Watch for melted tar picked up on hot road surfaces, which is best removed with a tar remover rather than scrubbing.
Cooling, Air Conditioning and Fluids
| Item | Summer point |
|---|---|
| Coolant | Antifreeze is a year-round coolant, raising the boiling point as well as lowering the freezing point. Check level cold and concentration annually |
| Radiator and condenser | Clear insects, leaves and debris from the front, which restricts airflow and causes overheating in traffic |
| Cooling fan | Confirm it cuts in; a failed fan shows up in stationary traffic rather than at speed |
| Air conditioning | If it blows warm, it likely needs regassing or has a leak. Run it regularly year-round to keep seals lubricated |
| Cabin pollen filter | Replace before hayfever season; it is inexpensive and frequently never changed |
| Oil | Check more often in hot weather and on long motorway runs |
| Screenwash | Consumption rises with insects and dust; keep it topped up with proper additive |
If the Temperature Gauge Rises
- Switch off the air conditioning and turn the cabin heater to hot with the fan on full, which draws heat out of the engine.
- Pull over safely and switch off if it continues to climb or a warning appears.
- Do not open the coolant cap while hot. Scalding pressurised coolant causes serious burns.
- Wait for it to cool before checking the level.
- Do not top up with cold water into a hot engine, which can crack components.
- Call for assistance if the cause is not obvious. Continuing on an overheating engine causes severe damage.
Paint, Trim and Interior
- Wash off bird droppings, tree sap and insects promptly. All etch paint, and heat accelerates it considerably.
- Do not wash in direct sunlight, which causes water spotting and makes products dry before you can remove them.
- Apply a wax or sealant before summer, which provides UV protection as well as gloss.
- Use a windscreen shade when parked, which protects the dashboard and makes the cabin bearable.
- Treat the dashboard with a matt product, never a glossy one, which reflects into the windscreen.
- Protect leather with a suitable conditioner; heat and UV dry and crack it.
- Park in shade where possible, which reduces UV damage and keeps the cabin usable.
The Driver in Hot Weather
Heat affects concentration and reaction time. Practical measures: carry water and drink it; plan longer journeys to avoid the hottest part of the day; take breaks at least every two hours as the Highway Code advises; use the air conditioning rather than enduring the heat; and wear sunglasses to reduce glare fatigue.
One point worth flagging: some hayfever antihistamines cause drowsiness, and driving while impaired by medication can constitute an offence. Check the packaging or ask a pharmacist, and choose a non-drowsy formulation if you are driving.
Regional Conditions and Local Provision
In the North West, motoring and transport coverage appears in the Manchester Chronicle and Liverpool Tribune, both cities operating air quality schemes affecting vehicles. Yorkshire motoring news is followed by Leeds Angle, Sheffield Voice and Bradford Daily.
Scotland, where some road traffic requirements and enforcement differ, is covered by Glasgow Bulletin and Edinburgh Scope, both with low emission zones. Northern Ireland, which operates its own vehicle testing arrangements, is reported by the Belfast Record.
Midlands motoring, including a substantial automotive manufacturing base, is covered by Birmingham Focus, Coventry Insight — historically the centre of British car manufacturing — plus Leicester Echo, Derby Digest and Nottingham Times. The Newcastle Brief and Hull Report cover the North East and Humber, including port and ferry routes.
Southern motoring and port traffic are reported by Brighton Update, Southampton Ledger, a major vehicle import port, plus Plymouth Wire and Bristol Outlook. London’s emission zones and congestion charging are covered by London Signals and Capital Outlook. Where driving affects work or mobility support, policy is followed via DWP UK Latest News, with automotive industry reporting in Trade Mirror.
Frequently Asked Questions
Do I need antifreeze in summer?
Yes. It is a coolant year-round, raising the boiling point as well as preventing freezing. Have the concentration checked annually.
Why is my air conditioning blowing warm?
Usually low refrigerant from a gradual leak, sometimes a component fault. It needs a proper diagnosis rather than simply topping up repeatedly.
Does heat damage a car battery?
Yes, and more than cold does over time. Heat accelerates internal degradation, and the failure then shows up on the first cold morning.
Can I leave a dog in the car with the windows open?
No. Interior temperatures rise rapidly and open windows make little difference. Never leave an animal or a child in a parked car.
Further Reading
Motoring, transport and consumer reporting appears across News Notes, Local News Point, Weekly Journal and Trends Archive. Garages, dealers and automotive businesses seeking coverage use agencies listed via Local PR Services, PR Directory and Press Hubs.
The Bottom Line
Never leave a child or animal in a parked car, for any length of time, in any circumstances. That is the most important thing on this page.
Then check tyre pressures cold and adjust for load, because underinflation plus heat plus motorway speed is what causes blowouts. Clear the radiator front, confirm the cooling fan works, and never open a hot coolant cap. Wash contaminants off paint promptly and use a windscreen shade.
This article is general information for UK drivers and is NOT legal, mechanical or road safety advice. Traffic law, MOT and roadworthiness requirements, and vehicle standards differ in some respects between England, Wales, Scotland and Northern Ireland and change over time. Keeping a vehicle in a roadworthy condition is a legal responsibility, and safety-critical work should be carried out by a qualified technician. Your vehicle handbook takes precedence over any general guidance here. Driver assistance systems support the driver and do not replace them. Verify current requirements with official sources, and consult a qualified mechanic or a solicitor as appropriate.
