1. Coolant Level: Check the coolant level in the reservoir. If it's low, add a 50/50 mix of water and antifreeze.
2.Thermostat: The thermostat may be stuck closed, preventing coolant from flowing to the heater core. This can be replaced.
3. Heater Core: The heater core may be blocked with debris or clogged. It needs to be cleaned or replaced.
4. Blend Door: The blend door may be stuck or broken, preventing hot air from flowing to the cabin. This needs to be repaired or replaced.
5. Heater Control Valve: The heater control valve may be stuck or faulty, preventing hot coolant from flowing to the heater core. It can be replaced.
6. Water pump: The water pump may be faulty, not circulating coolant properly. This needs to be replaced.
7. Clogged Hoses: The heater hoses may be clogged or kinked, restricting coolant flow. Replace them if necessary.
