Does the thermostat control heat in your car?

The thermostat does not directly control the heat inside the car. Instead, the thermostat has different settings that dictate when the coolant in your car's engine enters the heater core. The heater core is a small radiator located in the passenger compartment of the car. When the coolant flows into the heater core, a blower will push air over it, which heats up the air and is then blown into the cabin of the car. The thermostat controls when this heated air is allowed into the cabin by adjusting the flow of coolant to the heater core.