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♦ Vacuum pump (if there is one)
When evaluating the measuring results, bear in mind that they will
be influenced by the geographical location. The higher your lo‐
cation is above sea level, the lower the air pressure will be.
Before checking the vacuum system, please take note of the fol‐
lowing prerequisites for checking:
♦ Visual inspection of all vacuum hoses for damage (e.g. cracks
or marten bite) and to check that they are correctly and firmly
attached
♦ Ensure cleanliness when working on vacuum system
♦ Before starting work, clean engine compartment if necessary
Special tools and workshop equipment required
♦ Vacuum gauge for brake servo -VAS 6721-
6.4.1
Connecting vacuum gauge for brake
servo -VAS 6721-
– Pull vacuum hose out of brake servo.
First press the brake pedal several times in order to facilitate re‐
moval of the vacuum hose.
– Place brake servo vacuum gauge -VAS 6721- between them
-see following illustrations-.
Item
num‐
ber
Com‐
po‐
nent
Explanation
A
Cut-
off
valve
In direction of vacuum hose, non-return valve and,
if there is one, vacuum pump
B
Cut-
off
valve
♦ Open to facilitate removal of brake servo vac‐
uum gauge -VAS 6721-
♦ Open to simulate a fault source
♦ Connection of manual vacuum pump -VAS
6213-
C Cut-
off
valve
In direction of brake servo
Touareg 2010 ➤
Brake systems - Edition 05.2011
6. Brake servo vacuum supply
87
