Volvo VNL Operator's Manual page 335

330 Fifth Wheel Instructions
Wait about 30 seconds for the air springs to
deflate.
With the suspension lowered, pull clear of
the trailer and immediately select the
"RIDE" position (press the top part of the
switch in) on the suspension control. This
restores the suspension to operating height.
CAUTION
The vehicle must never be driven with
the air springs deflated. Damage to air
suspension parts will occur if springs are
not inflated properly.
After the trailer is uncoupled, the fifth
wheel will be in the open position. The op-
erating rod will drop and can be moved
around freely.
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