Can I directly add coolant if it's low?

[OFernando]

Yes, you can directly add coolant if it's low. The method for adding coolant is as follows: 1. Unscrew the radiator cap, open the radiator drain valve, and drain the coolant; 2. Insert a rubber hose into the radiator filler neck, then turn on the tap to flush the engine cooling system; 3. After draining all water from the cooling system, close the radiator drain valve; 4. Unscrew the reservoir cap and add coolant until the liquid level reaches the MAX mark; 5. Tighten the reservoir cap; 6. Start the engine and let it idle for 2-3 minutes, then unscrew the radiator cap to allow the cooling system to expel some air. The coolant level will drop, so add more coolant until it reaches the MAX mark again.