Check all hoses and connections. Check the cooling system for leaks as described below.
Level the coolant level, start the engine and let it idle.
Install a radiator fluid level gauge on the expansion tank instead of the threaded cap.
A sign of a leak is a low coolant level.
Leakage can be caused by fluid leaking through the outer seals, or by internal defects such as a leaking cylinder head gasket, cracks in the cylinder block or cylinder head.
Checking and adjusting the level and concentration of the coolant
The coolant level is checked with a cold engine. The coolant level must be between the MAX and MIN·marks.
If the level is below the MIN·mark, add the required amount of liquid of the appropriate concentration to the tank.
Do not exceed the coolant level.