Volvo VNL 780 Operator's Manual page 97

Optional Switch
8. Electronically Controlled Suspension (ECS) (Up/Down)
This is the switch that is defined by the body builder.
OR
Lift Axle
The vehicle may be equipped with auxiliary lift axles. The lift mechanism operates with air
pressure. Press the top part of the switch to raise the axle and press the lower part of the
switch to lower the axle. For information about lift axles, refer to "AXLES" page 378.
Pusher Axle
Tag Axle
OR
INSTRUMENTS AND CONTROLS
W3005503
W3005507
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