
For driving with a trailer, the yellow and red, if
equipped, knobs must be pushed in. When you are
not pulling a trailer, the red trailer air supply
knob must be pulled out.
{CAUTION:
If you apply any one of the air brake
parking controls while the vehicle is
moving, your rig will stop suddenly. If you
are not ready for this, you or others could
be injured. Do not apply any one of these
controls while you are driving, unless you
have to make an emergency stop.
If the air pressure drops below 60 to 70 psi
(413 to 482 kPa), the primary brake light and
warning buzzer will come on. If the air pressure
drops to 35 to 45 psi (241 to 310 kPa), the
red trailer air supply knob will automatically pop
out and apply the spring brakes on the trailer.If the air pressure drops to 35 to 45 psi
(241 to 310 kPa), the yellow park brake knob will
automatically pop out and apply the spring
brakes on the truck or tractor.
If you ever have a complete loss of air so that
your air brakes automatically apply, there is a way
that the tow operator can release the parking
brakes to tow the vehicle. SeeTowing Your
Vehicle on page 241.
Parking Brake Burnish Procedure
All vehicles which have hydraulic brakes will have
a parking brake. It is recommended that the
parking brake be burnished as part of the new
vehicle break-in. The parking brake will work best
after it has been burnished following these
instructions:
1. Making sure that there is no other traffic
around, get the vehicle speed up to
20 mph (32 km/h) and pull up to apply the
parking brake. Let the vehicle come to
a complete stop. Apply the base brakes and
disengage the parking brake.
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2. Repeat the burnishing procedure in Step 1 a
total of 10 times
3. Between stops, drive the vehicle about
2
1⁄2miles (4 km)
Notice:Driving with the parking brake on can
damage the transmission and brake system
parts. Verify that the parking brake is fully
released and the brake warning light is
off before driving.
Air Suspension
Your vehicle may have the Hendrickson HAS
Series single-axle air suspension which is
designed for a single-axle on-highway use. This
feature is available in 19,000 lb (8 613.3 kg),
21,000 lb (9 525.4 kg) and 23,000 lb (10 432.6 kg)
capacities.
Rear Air Suspension Dump Control
If your vehicle is equipped with the Hendrickson
HAS Series single-axle air suspension, you
may have this control. The air suspension dump
control allows the operator to lower the deck height
approximately 4.5 inches (11.5 cm) from the
normal frame height.
The switch to deflate
and inflate the air
suspension is located in
the instrument panel.
Press the bottom of the switch to deflate the air
suspension and lower the deck height. Press
the top of the switch to return the suspension to
normal deck height.
An indicator light will come on and stay on
whenever the switch is in the dumped position.
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Instrument Panel Overview........................ 140
Hazard Warning Flashers.......................... 142
Other Warning Devices............................. 142
Horn.......................................................... 142
Tilt Wheel.................................................. 142
Turn Signal/Multifunction Lever.................. 143
Turn and Lane-Change Signals................. 144
Headlamp High/Low-Beam Changer.......... 144
Windshield Wipers..................................... 145
Windshield Washer.................................... 146
Cruise Control........................................... 146
Exterior Lamps.......................................... 150
Headlamps on Reminder........................... 150
Daytime Running Lamps (DRL)................. 151
Marker Lamps........................................... 152
Instrument Panel Brightness...................... 152
Dome Lamps............................................. 153
Entry Lighting............................................ 154
Reading Lamps......................................... 154
Instrument Panel Switchbank..................... 154
Accessory Power Outlet(s)........................ 156
Ashtray(s) and Cigarette Lighter................ 157Climate Controls......................................... 157
Climate Control System............................. 157
Outlet Adjustment...................................... 160
Rear Heating System................................ 161
Warning Lights, Gages, and Indicators..... 161
Instrument Panel Cluster........................... 162
Speedometer and Odometer...................... 163
Trip Odometer........................................... 163
Tachometer............................................... 163
Engine Speed Limiter................................ 164
Safety Belt Reminder Light........................ 164
Safety Belt Reminder Tone....................... 164
Airbag Readiness Light............................. 165
Airbag Off Light......................................... 166
Charging System Light.............................. 167
Voltmeter Gage......................................... 168
Service Transmission Warning Light.......... 168
Range Inhibit Warning Indicator................. 169
Brake System Warning Light..................... 169
Anti-Lock Brake System Warning Light...... 172
Trailer Anti-Lock Brake System
Warning Light........................................ 172
Section 3 Instrument Panel
137

Engine Coolant Temperature Gage............ 173
Low Coolant Warning Light....................... 173
Wait to Start Indicator............................... 174
Malfunction Indicator Lamp........................ 174
Oil Pressure Gage..................................... 175
Low Oil Level Light................................... 176
Change Engine Oil Light........................... 176
Engine Overspeed Warning Light.............. 177
Engine Shutdown Warning Light................ 177
Transmission Temperature Gage............... 178
Exhaust Brake Indicator Light.................... 178
Differential Lock Indicator Light.................. 178
Reduced Engine Power Light.................... 179
Highbeam On Light................................... 179
Daytime Running Lamps (DRL)
Indicator Light........................................ 179
Low Washer Fluid Warning Light............... 180
Check Gages Warning Light...................... 180
Fuel Gage................................................. 181Water in Fuel Warning Light...................... 182
Air Filter Restriction Indicator..................... 182
Air Pressure Gage..................................... 183
Hourmeter Gage........................................ 183
Audio System(s)......................................... 184
Setting the Time........................................ 185
AM-FM Radio............................................ 186
Radio with Cassette.................................. 189
Radio with CD........................................... 195
Theft-Deterrent Feature
(Non-RDS Radios)................................. 201
Radio Reception........................................ 201
Care of the Cassette Tape Player............. 202
Care of Your CDs..................................... 203
Care of the CD Player.............................. 204
Fixed Mast Antenna.................................. 204
Chime Level Adjustment............................ 204
Section 3 Instrument Panel
138

A. Air Outlets. SeeOutlet Adjustment on
page 160.
B. Instrument Panel Cluster. SeeInstrument
Panel Cluster on page 162.
C. Shift Lever. SeeAutomatic Transmission
Operation on page 115orManual Transmission
Operation on page 116.
D. Air Brake Controls. SeeParking Brake (With
Hydraulic Brakes) on page 125orParking
Brake (with Air Brakes) on page 126.
E. Transfer Case Controls (If Equipped). See
Four-Wheel Drive on page 119. Air Filter Gage
(If Equipped). SeeAir Filter Restriction
Indicator on page 182.
F. Auxiliary Gages. SeeWarning Lights, Gages,
and Indicators on page 161.
G. Exterior Lamp Control. SeeExterior Lamps on
page 150.H. Turn Signal/Multifunction Lever. SeeTurn
Signal/Multifunction Lever on page 143.
I. Hazard Warning Flashers Button. SeeHazard
Warning Flashers on page 142.
J. Audio System(s). SeeAudio System(s) on
page 184.
K. Climate Controls. SeeClimate Control System
on page 157.
L. Instrument Panel Switchbank. SeeInstrument
Panel Switchbank on page 154.
M. Airbag Off Switch. SeeAirbag Off Switch on
page 76.
N. Accessory Power Outlets. SeeAccessory
Power Outlet(s) on page 156.
141

Rear Heating System
If you have a crew cab
and your vehicle has a
rear heater, the
thumbwheel for this
feature is located on
the headliner.
To increase and decrease the flow of heated air to
the rear floor vents, turn the thumbwheel to the
desired fan speed. To turn the fan off, turn
the thumbwheel all the way down.
Warning Lights, Gages, and
Indicators
This part describes the warning lights and gages
that may be on your vehicle. The pictures will
help you locate them.Warning lights and gages can signal that
something is wrong before it becomes serious
enough to cause an expensive repair or
replacement. Paying attention to your warning
lights and gages could also save you or others
from injury.
Warning lights come on when there may be or
is a problem with one of your vehicle’s functions.
As you will see in the details on the next few
pages, some warning lights come on briefly when
you start the engine just to let you know they
are working. If you are familiar with this section,
you should not be alarmed when this happens.
Gages can indicate when there may be or is a
problem with one of your vehicle’s functions. Often
gages and warning lights work together to let you
know when there is a problem with your vehicle.
When one of the warning lights comes on and
stays on when you are driving, or when one of the
gages shows there may be a problem, check
the section that tells you what to do about
it. Waiting to do repairs can be costly and even
dangerous.
161