Engine Coolant Circuit, Bleeding

• The removal of the heating and A/C system components is described in this Service Information in such a way that only a small amount of air enters the coolant circuit. Therefore, it is not necessary to completely drain and refill the coolant after removing and installing these components. It is sufficient to fill and bleed the coolant circuit. Refer to COOLANT, DRAINING AND FILLING .
• However, if a larger amount of coolant leaks out for another reason, for example, due to a leaking hose, then the coolant circuit must be completely drained. Refer to COOLANT, DRAINING AND FILLING .

Prerequisite 

-- The majority of the coolant circuit is filled with coolant; there are only a few air bubbles at a few locations of the cooling circuit.

-- Drain and fill the coolant circuit. Refer to COOLANT, DRAINING AND FILLING .