An operating permit is available for the brake system of the
vehicles. This licensing becomes invalid if the brake system is
modified.
Load-related
brake proportioning valve
(only for front-wheel drive)
The load-related brake proportioning valve is conceived for
adjusting the brake pressure at the
rear axle to the respective load condition and is controlled
according to the spring suspension
at the rear axle.
The load-related brake proportioning valve is provided ex-works
with a regulation, based on a
tension spring, relating to the unladen weight of the vehicle.
Usually, it is not required to
re-adjust this regulation - not even after mounting an attachment
onto the chassis.
In special cases - for example retrofitting of reinforced
springs, mounting of an unusually
lightweight attachment - it is required to correct the regulation
of the brake proportioning valve.
The pressure check and regulation should be carried out at a
Volkswagen dealer/workshop for
utility vehicles. The regulation has to be performed in such a
way that the balance beam is
horizontal.
Modifications of the brake system are illegal!
Exceptions are the adaptation of the brake-pressure line and the
handbrake cable in the
scope of wheel base changes at chassis.
Volkswagen
AG
Automatic brake pressure regulator
Check:
Test:
Inlet pressure on front axle
wheel cylinder bleeder valva
Mean value from left
and right
Outlet pressure on rear axle
wheel cylinder bleeder valva
Output
pressure
(bar)
Rear axle load Input pressure
(kg)
(bar)
500
600
650
700
750
50
50
50
50
50
14±2
14±2
15±4
19±5/2
24±6/4
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English 