gets heat into the cockpit the same way as all other cars: through a Mercedes heater core. Hot engine coolant circulates through the Mercedes heater core under your dashboard, warming up the HVAC air flowing over it. The upside of using a Mercedes heater core is that no additional fuel or electricity is consumed heating your interior. The downside of the Mercedes heater core design is that boiling hot, toxic coolant is flowing through your vehicle just inches from your feet. Don't worry too much: If Mercedes heater core explosions were common, they'd have changed the design decades ago. It would take a fairly substantial blockage to cause a Mercedes heater core to burst. Much like a radiator, though, the Mercedes heater core will develop tiny leaks over time. Particularly if the coolant isn't changed periodically, the Mercedes heater core will corrode from the inside out. Eventually some of the coolant will find a way to seep out of the Mercedes heater core, and you end up with green stains on your wool carpet...or worse, on your leather loafers. The staining is a pain, but if a Mercedes heater core leak goes unnoticed worse things can happen. Water is the major component of engine coolant, and if that coolant leaks from your Mercedes heater core onto the floorpans, you can have a ton of rust develop before you notice the problem. The rule of thumb is to check your coolant periodically to make sure it isn't low (which would indicate a leak) and change the coolant every other year or at the manufacturer's scheduled intervals. This way your Mercedes heater core will live a long life and you'll catch it before a catastrophic failure occurs.