How do you replace heater core on 2004 suzuki aerio?

To replace the heater core on a 2004 Suzuki Aerio, start by disconnecting the battery and draining the coolant. Remove the dashboard and center console to access the heater core housing. Disconnect the hoses and any electrical connections, then unbolt the heater core from its housing and replace it with the new unit. Finally, reassemble the dashboard, reconnect the battery, and refill the coolant.