Suspension/Trailer Connection
Controls
Air Suspension Dump Control Switch
NOTICE
Do not operate the vehicle over uneven ground
such as ramps, speed bumps, curbs, etc. with
the air springs deflated. Doing this may lead to
air bag separation from the piston, preventing the
suspension air springs from re-inflating.
The air suspension height control switch may be
used to aid in connecting or disconnecting from a
trailer. When the switch is set to LOWER, the air
suspension dump valve deflates the air springs to
lower the rear of the vehicle. In the AUTO position,
the automatic ride-control valves operate for normal
driving.
NOTICE
Never exhaust air from the suspension while
driving. When the air is exhausted, the suspen-
sion will not absorb road shocks, and compo-
nents may be damaged.
A red LED in the switch is illuminated when the sus-
pension is deflated.
Fifth Wheel Slide Control Switch
NOTICE
Do not activate the fifth wheel slide control valve
while the vehicle is in motion. To do so could
cause damage to the fifth wheel member, the
kingpin, the cab or trailer, and ultimately to the
drivetrain.
The fifth wheel air slide valve allows repositioning of
the sliding fifth wheel from inside the cab. Move the
air slide control valve switch to the LOCK position to
lock the fifth wheel to the baseplate. Move the switch
to the UNLOCK position to unlock the fifth wheel
slide mechanism, allowing changes to the total length
of the tractor-trailer and changes to axle loads to
comply with state or provincial laws.
For detailed operating instructions for fifth wheel
slide, refer to
Chapter 10
. A red indicator light illumi-
nates whenever the fifth wheel slide is unlocked.
Trailer Auxiliary Switch
Some trailers with pneumatic brakes are equipped
with power for the trailer lights. The connection is
passed from the vehicle to the trailer via the primary
receptacle, controlled by a dash switch.
Press the top of the switch to activate the trailer aux-
iliary function. Press the bottom of the switch to turn
trailer auxiliary function off.
Windshield Wiper/Washer Controls
NOTICE
Do not attempt to manually move the windshield
wiper arms. Wiper motor damage will occur if the
arms are forcibly moved.
The wipers are operated by a dual paddle switch lo-
cated on the auxiliary instrument panel. See
Fig. 2.27
. To turn the wipers on or off, press the top
paddle in. When the top paddle is pushed up, the
wipers will operate at high speed; when it is pushed
down, they will wipe at low speed.
The bottom paddle, when pushed in, turns the
washers on. When pressed for less than ½-second,
the wipers will perform a single, low speed dry wipe
(mist function). When pressed for more than
½-second, the wash cycle begins and continues for
three cycles or until the paddle is released. When the
bottom paddle is pushed up, the wipers operate in
fast delay. When the bottom paddle is pushed down,
the wipers operate in slow delay. With the wipers in
delay mode (fast or slow), push the bottom paddle
up to shorten the delay period, or push the paddle
down to lengthen it.
05/01/2012
f611185
Fig. 2.27, Windshield Wiper Switch
Instruments and Controls Identification
2.25
