OPERATOR'S MANUAL

DASH- AND DOOR-MOUNTED FEATURES CONTROLS AND DISPLAY
– 54 – Y53-6027
Medium Duty (R05/09)
Fog Lights Switch
If your vehicle has fog lights, turn them ON or OFF with
the control panel switch with the symbol shown above.
NOTE: Across the U.S.A. and Canada, State/Pro-
vincial requirements vary as to when high beams
and fog lights can and cannot be used together.
Some states allow only four lights to be used
together, while some allow more. How your lights
are arranged will affect whether you can operate
headlights and fog lights concurrently—always
comply with the state or provincial requirements
where you are driving.
Air Suspension Deflate Switch (Dump Valve)
Your Peterbilt vehicle may have an air suspension defla-
tion switch which allows the air in the suspension to be
exhausted from a switch on the dash. The purpose of this
feature is to allow you to lower your tractor to get under a
trailer. You may notice a guard over the switch. This pre-
vents you from accidentally deflating the suspension.
WARNING! Operating the Air Suspension
Deflate Switch (Dump Valve) while driving can
lead to an accident causing death or personal
injury. Sudden deflation while your vehicle is
moving can affect handling and control. Use
this switch only when your vehicle is not mov-
ing.
AIR SUSPENSION