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– After generation of vacuum, close cut-off valve -A- in order to
check brake servo vacuum system.
Vacuum check in vicinity of non-return valve, vacuum hoses with
connectors and vacuum pump/intake pipe:
– After generation of a vacuum, close cut-off valve -C- in order
to check vacuum system from brake servo vacuum gauge -
VAS 6721- to intake pipe or to vacuum pump.
Open cut-off valve -B- to facilitate removal of hose connections
and adapter.
6.4.4
Vacuum generation with manual vac‐
uum pump -VAS 6213-
Instead of vacuum generation by means of engine or vacuum
pump, the vacuum can be generated with the manual vacuum
pump -VAS 6213- in certain cases.
– To do this, connect manual vacuum pump -VAS 6213- to vac‐
uum hose from connection -B- on brake servo vacuum gauge
-VAS 6721- .
– Open cut-off valve -B-.
– Generate vacuum with hand vacuum pump -VAS 6213- until
between 600 and 950 mbar is shown on brake servo vacuum
gauge -VAS 6721- .
– Then, carry out the corresponding checks.
6.5
Checking non-return valve
Air must pass through valve in direction of arrow.
Valve must remain closed in opposite direction.
Observe correct installation position.
Touareg 2010 ➤
Brake systems - Edition 05.2011
90
Rep. gr.47 - Brakes - hydraulics
