Many drivers are unaware their car key may already have a built-in feature that can help cool the vehicle before they get behind the wheel. By holding down the unlock button on many modern car keys, all windows lower automatically, allowing trapped hot air to escape before the door is even opened. This function, known as 'global opening' or 'convenience opening', can begin cooling the interior almost immediately.
How the Hidden Feature Works
The trick relies on a feature available in many modern vehicles, though it is not fitted to every make or model. Drivers are advised to check their owner's manual, as some manufacturers require the feature to be activated through the car's settings. It proves particularly useful during periods of hot weather, when the temperature inside a parked vehicle can rise much faster than the air outside. According to the RAC, opening windows and doors before setting off is one of the quickest ways to release built-up heat and improve airflow.
Expert Recommendations for Hot Cars
The AA also recommends ventilating a hot vehicle before driving away, rather than relying solely on air conditioning. It says allowing trapped hot air to escape first can make the cooling system more effective and improve comfort behind the wheel. The advice comes as parts of the UK continue to experience exceptionally high temperatures. The Met Office has issued a red weather warning for heat affecting various parts of the UK, with the mercury rising as high as 38°C.
Safety Reminders During Heatwaves
While the hidden window feature can help make the car interior more comfortable, it should never be seen as a substitute for proper heat safety. The NHS advises avoiding prolonged periods in hot, enclosed spaces where possible and stresses the importance of staying cool and well hydrated during periods of extreme heat. Experts also remind motorists never to leave children, older adults or pets inside a parked vehicle, even for a short time. According to the RSPCA, temperatures inside a car can become fatal within minutes, even if a window has been left slightly open.
