You’re running late. It’s before 7am, still dark, and your car windscreen is icier than the ski racks at Falls Creek on the King’s Birthday long weekend. You grab a credit card and a bottle of water, crank the wipers up to 11, and clear the decks. You can’t feel your fingers, your new work shirt is wet and now you’ve got a foggy windscreen too! Sound familiar?
Melbourne’s winter mornings are no joke, and neither are foggy windscreens! If your windscreen is taking forever to clear – or is constantly fogging back up – you’re not alone, and your car might be trying to tell you something.
Why your windscreen is foggy or freezes
It’s the winter morning double-whammy and the auto-equivalent of a tongue-twister for a weather presenter: frost and frog. But what causes it?
- Frosted outside: cold overnight temperatures and moisture = ice crystals
- Foggy inside: warm and moist air (yep, that’s you, your morning coffee and your warm breath…) hitting a cold windscreen = condensation
Both are annoying, but fog on the inside? Well that’s often the harder one to shift, especially if your demister or heating system isn’t pulling its weight.
The fastest way to clear it up
- Pour lukewarm water on the outside – never hot!
Gently pouring lukewarm water on your windscreen while your wipers go to work can help melt the frost without cracking your windscreen. Just make sure you stand clear of the water! - Use your demister setting
Your demister setting will typically activate both the heater (to warm your frozen fingers!) and the A/C (to dry the air). Having the A/C on might feel counter-intuitive, but we’re combatting humidity here, so we can clear things faster by hitting it with dry, warm air. If you’re driving an older model, check that the A/C setting is lit up – you may need to switch it on manually. - Open a window slightly
This helps balance the humidity and stops your breath from fogging things up again straight after it clears. - Check for recirculation
Make sure the air is coming from the outside – using recirculated air keeps moisture trapped inside the vehicle, which is a recipe for a foggy windscreen! - Don’t do it…don’t do it…don’t…wipe the windscreen with your hand / sleeve / scarf!
I know you want to…but trust me on this! You’ll just smear the fog and leave oil behind, which fogs up even worse later. If you must wipe, use a microfibre cloth.
Windscreen still foggy? Your car might need a hand
If your foggy windscreen persists no matter what you do, there could be something else going on. Here’s some common issues we see here at Cox Auto as we head towards those cold mornings.
A faulty blower fan
If the fan’s on its last legs, you won’t get enough airflow to properly demist, no matter how high you crank the settings. Is the airflow in your vehicle’s cabin weak or inconsistent? Can you hear a slapping or whirring sound that increases in frequency as you turn up the fan? Your heater fan may be the culprit.
Low coolant or a faulty heater core
Your windscreen won’t demist without warm air, and that depends on a working heater core and proper coolant levels. If you’re only get cold or weak air, it’s time to get it checked. A coolant leak can be an indicator of a more serious issue with your radiator or radiator hose; it’s something to get on top of early before you find yourself on the side of the road.
Hidden moisture from leaks or damp interiors
Leaks around windows, doors, or from the heater system can trap moisture in your carpets or underlays. That trapped humidity becomes fog when the temperature drops. Recently had the car steam cleaned? Left your wet training gear in the backseat? Moisture might be your problem.
Pro tip: keep your windscreen clean
Grime and fog are like mischief and mayhem. One invites the other! A clean windscreen inside and out fogs up less and clears faster. Lucky every service with Cox Auto includes a FREE wash, clean and vac then!
We’ll help you see clearly this winter
Whether you’re heading to school drop-off, crawling along Kings Way to the office, or picking up weekend pastries on Clarendon Street, one thing’s for sure – a fogged up windscreen shouldn’t be part of your morning routine. If things aren’t clearing like they should, book in with Cox Auto. We’ll check your heater, filters, and vents and get everything running the way it should.
No more scraping. No more wiping. Just clear views and cosy drives.
