What Is a Heater Core?
The heater core is a little radiator that warms your cabin — and causes distinctive problems when it fails. A Cranbourne West specialist explains.
What it is & what it does
The heater core is a small radiator behind the dashboard. Hot engine coolant flows through it, and the cabin fan blows air across it to heat the car. Blend doors control how much air passes through it.
It’s plumbing hot coolant inside your dash — which is why its failures are so recognisable.
Signs of trouble & how we help
A blocked core gives weak or no heat. A leaking core gives a sweet smell inside, fog on the windscreen that’s hard to clear, damp carpet on the passenger side, and dropping coolant. Access is buried, so accurate diagnosis before pulling a dash matters.
We pressure-test to confirm the core (vs hoses or a blend-door fault) before any big labour.
Questions about your car? Just ask.
Understanding what’s under the bonnet makes servicing decisions easier — and we’re always happy to explain what your car needs and why, in plain English.
Book a service or a check with a Cranbourne West specialist online in 60 seconds, or call 03 8782 0711.
What Is a Heater Core? — FAQ
It’s a small radiator behind the dash — hot coolant flows through and the fan blows air across it to heat the cabin.
A sweet smell inside, stubborn windscreen fog, damp passenger-side carpet, and coolant loss.
It’s buried behind the dash — labour-heavy, which is why we confirm the diagnosis first.
A blocked core, airlock, thermostat or blend-door fault — we test which. See our no-heat guide.
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