Warning indication of air pressure drop
Air brakes of trailers and semi-trailers
PGPPN137
Air brakes of trailers (semi-trailers) and brakes of the tractor are designed so that braking effects of both
vehicles are synchronised.
In case of a drop of pressure the transfer valve disables the secondary consumers (differential
lock, disengagement of the front driving axle).
When driving with a trailer or semi-trailer the foot brake pedals shall be coupled and secured by
a latch!
With braking by one brake pedal the trailer air brakes are not activated.
Decrease of air pressure below 450 kPa is indicated by
activation of the red signal lamp on the instrument panel.
The tractor with the braked trailer or semi-trailer
during pressure decrease in the air-pressure system
below 450 kPa must not continue in operation until
increase of air pressure occurs.
More information in chapter INSTRUMENT PANEL.
P18N013