Coolant: Service and Repair

03 - Service Procedures


Cooling System, Checking Freeze Protection and Coolant Level

• Only G12 conforming to TL VW 774 F my be used as an additive. It can be recognized by the purple color.

• G 12 purple (according to TL VW 774 F) can be mixed with the previous coolant additives G 11 and G 12 (red).

• G 12 purple (according to TL VW 774 F) may be mixed with previous coolant additive G 12 red.

G 12 and coolant additives marked "In accordance with TL VW 774 F" prevent freezing and corrosion damage, scaling and also raise the boiling point of the coolant. For these reasons, the cooling system must be filled with radiator freeze and corrosion protection fluid all year round.

Checking freeze protection and adding coolant additive if necessary.

• Coolant Level, Checking and Filling

Freeze Protection, Checking and Adding Coolant Additive

Special tools, testers and auxiliary items required

• Refractometer (T10007)





• Read the bright/ark boundary to obtain an accurate reading for the following tests. Place a drop of water on the glass to improve the readability of the bright/dark boundary. The bright/dark boundary can be clearly recognized on the "WATERLINE".

- Check the concentration of the coolant additive using refractometer (T10007) (operating instructions).

The scale - 1 - of the refractometer is designed for coolant additives -G 12- and -G 11-.





• Freeze protection must be guaranteed to approximately -25 °C (approximately -35 °C in countries with an arctic climate).

• If climate conditions make greater freeze protection necessary, the amount of G 12 can be increased up to 60% (Freeze protection to approximately -40 °C). Adding more coolant reduces the freeze protection and reduces the cooling efficiency.

- If freeze protection is insufficient, drain off required quantity shown in freeze protection table and add coolant additive -G 12- which corresponds to TL VW 774 F.

Coolant Level, Checking and Filling

- Check the coolant level in the coolant reservoir with the engine cold.

• Delivery inspection: coolant level at max. marking - arrow -





• Inspection service: coolant level between the min. and max. marks.

- If coolant level is too low, fill with coolant mixture.

• If fluid losses are greater than can be reasonably expected, rectify malfunctions.

Mixture Ratio





• Coolant additive -G 12- according to TL VW 774 F prevents freezing and corrosion damage, scaling and also raises boiling point of coolant. For these reasons, the cooling system must be filled with radiator freeze and corrosion protection fluid all year round.

• Especially in countries with tropical climates or when vehicle is driven under heavy load, the coolant improves the engine reliability by its increased boiling point.

• The coolant concentration must not be reduced by adding water, even during the warmer season. The coolant additive ratio must be at least 40%.

Freeze protection table





• Observe waste disposal regulations!

- Check freeze protection ratio once more after road test.