Tiguan 2016 ➤, Tiguan 2021 ➤, Tiguan RUS 2017 ➤, Tiguan RUS 2021 ➤
Maintenance - Edition 12.2020
4.30
Cooling system for high-voltage sys‐
tem: checking coolant additive and
coolant level
Note
♦ The water used for mixing has a major influence on the ef‐
fectiveness of the coolant. Because the water quality differs
from country to country and even from region to region, the
quality of the water to be used in the cooling system has
been specified by Volkswagen. Distilled water satisfies all
requirements. Therefore, only ever use distilled water when
mixing coolant for topping up or renewing coolant.
♦ Use only coolant additives which conform with the ⇒ Elec‐
tronic parts catalogue (ETKA). Other coolant additives may
reduce corrosion protection substantially. The resulting dam‐
age could lead to loss of coolant and subsequent severe
damage to the engine.
♦ Mixed in the proper proportions, coolant inhibits frost and
corrosion damage as well as scaling. Additives also raise the
boiling point of the coolant. Therefore, the cooling system
must be filled all year round with a coolant additive.
♦ Because of its high boiling point, the coolant improves en‐
gine reliability under heavy loads, particularly in countries
with tropical climates.
♦ The refractometer -T10007A- or refractometer -T10007B-
must be used to determine the current anti-freeze value.
♦ Scale -1- of the refractometer is calibrated for the coolant
additives G12++ and G12evo.
♦ Scale -2- of the refractometer is calibrated for the coolant
additive G13.
♦ If it is not possible to ensure that the same type of coolant
additive is filled: always determine anti-freeze protection us‐
ing the scale for G13.
♦ Frost protection must be guaranteed down to -25°C as a
minimum and, in countries with arctic conditions, down to
approx. -36°C. Increasing the frost protection is permissible
only if climatic conditions require stronger frost protection. It
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4. Descriptions of work
Tiguan 2016 ➤, Tiguan 2021 ➤, Tiguan RUS 2017 ➤, Tiguan RUS 2021 ➤
Maintenance - Edition 12.2020
may, however, be increased only to a maximum of -48°C.
Otherwise, the cooling effect will be impaired.
♦ The coolant concentration must not be reduced by adding
water even in warmer seasons and in warmer countries.
Frost protection must be guaranteed down to at least -25°C.
♦ The temperature reading on the refractometer corresponds
to the »ice flocculation point«. Flakes of ice may start form‐
ing in the coolant below this temperature.
♦ Never reuse old coolant.
♦ Use only a water/coolant additive mixture as a slip agent for
coolant hoses.
4.30.1
Coolant level: checking, replenishing
coolant if necessary
NOTICE
If the coolant expansion tank is sealed with a lead seal -1-,
seal it again after checking or replenishing the coolant level.
– Check coolant level in coolant expansion tank with engine
cold.
1 - Pre-delivery inspection
Coolant level at lower edge of welded rim -3- of coolant expan‐
sion tank or above:
– No activity required, coolant level OK.
Coolant level between lower edge of welding rim -3- and “MIN.
mark” -4- of coolant expansion tank:
– Replenish coolant up to “max. mark” -2-.
– Fit a new lead seal to coolant expansion tank.
Coolant level below “min. mark” -4-.
– Check cooling system for leaks ⇒ 4-cyl. injection engine (hy‐
brid); Rep. gr. 19; Cooling system/coolant.
– Replenish coolant up to “max. mark” -2-.
– Fit a new lead seal -1- to coolant expansion tank.
2 - 1st oil change service at 15,000 km or after 1 year
Coolant level at “MAX. marking” -2-:
– No action necessary.
4. Descriptions of work
89
Tiguan 2016 ➤, Tiguan 2021 ➤, Tiguan RUS 2017 ➤, Tiguan RUS 2021 ➤
Maintenance - Edition 12.2020
Coolant level between “MIN. marking” -4- and “MAX. marking”
-2-:
– Replenish coolant up to “max. mark” -2-.
– Fit a new lead seal to coolant expansion tank.
Coolant level below “min. mark” -4-.
– Check cooling system for leaks ⇒ 4-cyl. injection engine (hy‐
brid); Rep. gr. 19; Cooling system/coolant.
– Replenish coolant up to “max. mark” -2-.
– Fit a new lead seal -1- to coolant expansion tank.
4.30.2
Frost protection: checking, replenishing
coolant additive if necessary
Special tools and workshop equipment required
♦ Refractometer -T10007A-
♦ Refractometer -T10007B-
Note
Read precise value for the following tests at light-dark border.
Using a pipette, place a drop of water on the glass to improve
the readability of the light-dark border. The light-dark border can
be clearly recognised on the “WATERLINE”.
– Check concentration of coolant additive using refractometer
(refer to operating instructions).
Scale -1- of the refractometer is calibrated for the coolant addi‐
tives G12++ and G12evo.
Scale -2- of the refractometer is calibrated for the coolant addi‐
tive G13.
– If frost protection is insufficient, drain some coolant and top
up with coolant additive ⇒ page 89 .
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4. Descriptions of work
Tiguan 2016 ➤, Tiguan 2021 ➤, Tiguan RUS 2017 ➤, Tiguan RUS 2021 ➤
Maintenance - Edition 12.2020
Note
♦ If the currently used coolant additive cannot be determined
precisely, use the scale -2- for coolant additive G13.
♦ Please observe disposal instructions!
– Check coolant additive concentration after road test again.
4.30.3
Mixing ratio
NOTICE
Use only distilled water for mixing coolant additives. The use
of distilled water ensures optimum protection against corro‐
sion.
Anti-freeze protection to
Coolant additive
portion
Distilled water
-25°C
-36°C
approx. 40%
approx. 50%
approx. 60%
approx. 50%
4.31
Diesel fuel filter: draining
Note
Applies only to vehicles with PR number 1A8.
Description of work
NOTICE
Ensure that no diesel fuel contacts other components in the
engine compartment. Clean immediately, if necessary.
Observe relevant disposal regulations.
Note
Please observe disposal instructions!
– Fit a suitable hose onto banjo bolt -arrow-.
– Start the engine.
4. Descriptions of work
91

2024 VW Tiguan Owner's Manual