There are many reasons that the heating system in a car is not working. Here are the simple but most effective fixes when the heating system fails.
1. A coolant leak into the engine
When the car heating system is not working, check whether there is a leak of coolant in the engine, check the cooling water level in the car is reduced. Because when the car engine is seeped or leaked, coolant will make the heating system inoperable.
2. The engine temperature controller is stuck
The engine temperature controller is responsible for controlling the warming of the engine while driving. If the unit is stuck open, the engine is on low heat and as such will not be able to generate heat to the heating system causing the system to malfunction. Remove and check the thermostat to make sure it is not stuck or damaged.
3. Gas mixing door actuator error
The electronically controlled hot air control door unit in the heater compartment may be damaged. Check the hot and cold blended door actuator in the heater system and replace it to correct the damage.
4. Clogged hot control valve
The hot control valve in the vehicle’s heating system can become clogged which prevents coolant from entering the heater core with the air conditioning function preventing the heating system from working. Check this control valve to make sure it is not clogged.
5. Open the vacuum line of the heating system
When the heating vacuum line leaks, steam passing through the hot control valve will render the heating system inoperable. This vacuum line leak is manifested by a hissing noise in the system while the engine is running.
6. The heating core is damaged
The heating core converts the coolant into the hot air, and if damaged, the system will not run. To check heater core damage, start the car to warm to normal temperature. You check two heating pipes, both pipes are hot, the part is not faulty, if only one is hot, make sure the heater core or control valve is damaged and needs to be replaced.
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