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Air Conditioning with Dual Zone Temperature
Control — If Equipped
With the Dual Zone Temperature Control System, each
front seat occupant can independently control the tem-
perature of air coming from the outlets on their side of
the vehicle. Air Conditioning and Heating Operation
To turn on the Air Conditioning, set the fan control at any
speed and press the snowflake button located on the
control panel. Conditioned air will be directed through
the outlets selected by the mode control. A light in the
snowflake button shows that the air conditioning is on.
Press the button a second time to turn the air condition-
ing off.
A/C Pushbutton
With the fan control in the ON posi-
tion, pushing the A/C button turns on
the air conditioning compressor. An
indicator light on the button shows
that the Air Conditioning compressor
is on. Conditioned air is now directed
through the mode outlets selected.
Pushing the button a second time turns the compressor
OFF.Dual Zone Control Head236 UNDERSTANDING YOUR INSTRUMENT PANEL
Page 241 of 532

Regular cleaning of the inside of the windows with a
non-filming cleaning solution (vinegar and water works
very well) will help prevent contaminates (cigarette
smoke, perfumes, etc.) from sticking to the windows.
Contaminates increase the rate of window fogging.
Summer Operation
Air conditioned vehicles must be protected with a high
quality antifreeze coolant during summer to provide
proper corrosion protection and to raise the boiling point
of the coolant for protection against overheating. A 50 %
concentration is recommended. Refer to Recommended
Fluids and Genuine Parts for the proper coolant type.
When using the air conditioner in extremely heavy traffic
in hot weather especially when towing a trailer, addi-
tional engine cooling may be required. If this situation is
encountered, operate the transmission in a lower gear to
increase engine RPM, coolant flow and fan speed. When stopped in heavy traffic, it may be necessary to shift into
NEUTRAL and depress the accelerator slightly for fast
idle operation to increase coolant flow and fan speed.
NOTE: On models equipped with Diesel engines, the
idle speed will automatically increase to 1000 rpm at
elevated coolant temperatures to improve engine cooling.
Your air conditioning system is also equipped with an
automatic recirculation system. When the system senses
a heavy load or high heat conditions, it may use partial
Recirculation A/C mode to provide additional comfort.
Winter Operation
When operating the system during the winter months,
make sure the air intake, located directly in front of the
windshield, is free of ice, slush, snow, or other obstruc-
tions. UNDERSTANDING YOUR INSTRUMENT PANEL 241
4
Page 244 of 532

▫ Operating Precautions ..................263
▫ Cooling System Tips — Automatic Transmission 263
Engine Block Heater — If Equipped .........265
Diesel Exhaust Brake (Engine Braking) – If
Equipped ............................265
Automatic Transmission ..................266
▫ Automatic Transmission With Overdrive (5 Speed
545RFE) — If Equipped .................267
▫ Automatic Transmission (6 Speed AS68RC) — If
Equipped ...........................273
Manual Transmission ....................279
▫ Manual Transmission — 6 Speed (G56) ......280
▫ Recommended Vehicle Shift Speeds ........280
▫ Downshifting – Gas Engine ..............281 ▫ Downshifting – Diesel Engine ............282
Four-Wheel- Drive Operation — If Equipped . . . 283
▫ Manually Shifted Transfer Case Operating
Information/Precautions ................283
▫ Shifting Procedure - Manually Shifted Transfer
Case ..............................286
▫ Transfer Case Reminder Light ............287
▫ Electronically Shifted Transfer Case Operating
Information/Precautions (4 Position Switch)—If
Equipped ...........................288
▫ Shifting Procedure - Electronically Shifted Transfer
Case ..............................292
Limited-Slip Differential — If Equipped .......295
Power Take Off Operation – If Equipped ......296
▫ Stationary Mode ......................296244 STARTING AND OPERATING
Page 252 of 532

Manual Transmission – If Equipped
Apply the parking brake, place the gearshift control lever
in NEUTRAL and depress the clutch pedal to the floor
before starting the vehicle. This vehicle is equipped with
a clutch interlocking ignition system. It will not start
unless the clutch is fully depressed.
Automatic Transmission – If Equipped
Start the engine with the selector lever in NEUTRAL or
PARK position. Apply the brake before shifting to any
driving range.
The Cummins Diesel engine is equipped with several
features designed to assist cold weather starting and
operation:
• The engine block heater is a resistance heater installed
in the water jacket of the engine just above and behind
the oil filter. It requires a 110–115 volt AC electrical
outlet with a grounded, three-wire extension cord. NOTE: The engine block heater cord is a factory in-
stalled option. If your vehicle is not equipped, heater
cords are available from your authorized Mopar dealer.
• A 12–volt heater built into the fuel filter housing aids
in preventing fuel gelling. It is controlled by a built-in
thermostat.
• A heated intake air system both improves engine
starting and reduces the amount of white smoke
generated by a warming engine.
Normal Starting Procedure — Engine Manifold
AirTemperature Above 66°F (19°C)
Observe the Instrument Panel Cluster lights when start-
ing the engine.
1. Always apply the parking brake.
2. Shift into PARK for an automatic transmission. Fully
depress and hold the clutch and shift into NEUTRAL for252 STARTING AND OPERATING
Page 253 of 532

a manual transmission. Models with manual transmis-
sion are equipped with a clutch interlocking cranking
system. The clutch must be fully depressed to start the
vehicle.
3. Turn the ignition key to the ON position and look at
the instrument panel cluster lamps.
CAUTION!If WATER IN FUEL indicator light remains on DO
NOT START engine before you drain water from the
fuel filter to avoid engine damage. See Section 7 —
Maintaining Your Vehicle, for water drain proce-
dures.
4. Turn the ignition key to START and crank the engine.
Do not press the accelerator during starting. CAUTION!Do not crank engine for more than 15 seconds at a
time as starter motor damage may result. Turn key to
OFF and wait at least two minutes before trying
again.
5. When the engine starts, release the key.
6. Check to see that there is oil pressure.
7. Release the parking brake.
Starting Procedure — Engine Manifold Air
Temperature Below 66°F (19°C)
NOTE: The temperature displayed on the overhead
console (if equipped) does not necessarily reflect the
engine manifold air temperature. When certain engine
temperatures fall below 66°F (19°C) the lamp will remain
on indicating the intake manifold heater system is active. STARTING AND OPERATING 253
5
Page 254 of 532

Follow the steps in the Normal Starting Procedure ex-
cept:
CAUTION!Do not crank engine for more than 15 seconds at a
time or starter motor damage may result. Turn key to
OFF and wait at least 2 minutes for starter to cool
before repeating start procedure.
• The WAIT TO START light will remain on for a period
of time (length of time depends on engine tempera-
ture).
• After the WAIT TO START light goes off, turn the
ignition key to START. Do not press the accelerator
during starting.
• After engine start-up, check to see that there is oil
pressure. • Allow the engine to idle about three minutes until
the manifold heaters have completed the post-heat
cycle.
• Release the parking brake and drive.
NOTE: Engine idle speed will automatically increase to
1000 rpm at low coolant temperatures to improve engine
warm-up.
NOTE: If the engine stalls or if the ignition switch is left
On for more than 2 minutes after the WAIT TO START
light goes out, reset the grid heaters by turning the
ignition switch to Off for at least 5 seconds and then back
On. Repeat steps 3 through 7 of the normal starting
procedure.
For Extremely Cold Weather Starting — Engine
Manifold Air Temperature Below 0°F (- 18°C)
In extremely cold weather below 0°F (- 18°C) it may be
beneficial to cycle the manifold heaters twice before254 STARTING AND OPERATING
Page 255 of 532

attempting to start the engine. This can be accomplished
by turning the ignition OFF for at least 5 seconds and
then back ON after the WAIT TO START light has gone
off, but before the engine is started. However, repeated
cycling of the manifold heaters will result in damage to
the heater elements or reduced battery voltage.
NOTE: If multiple pre-heat cycles are used before
starting, additional engine run time may be required to
maintain battery state of charge at a satisfactory level.
• If the engine stalls after the initial start, the ignition
must be turned to the OFF position for at least 5
seconds and then to the ON position to recycle the
manifold heaters.
NOTE: Excessive white smoke and poor engine perfor-
mance will result if manifold heaters are not recycled.
• Heat generated by the manifold heaters dissipates
rapidly in a cold engine. If more than two minutes pass between the time the WAIT TO START light goes
OFF and the engine is started, recycle the manifold
heaters by turning the ignition OFF for at least 5
seconds and then back ON.
• If the vehicle is driven and vehicle speed exceeds 19
mph (31 km) before the manifold heater post-heat
(after start) cycle is complete, the manifold heaters will
shut off.
• If the engine is started before the WAIT TO START
light turns off, the preheat cycle will turn off.
• If the engine is cranked for more than 10 seconds, the
post-heat cycle will turn off.
NOTE: Engine idle speed will automatically increase to
1000 rpm at low coolant temperatures to improve engine
warm-up. STARTING AND OPERATING 255
5
Page 257 of 532

Starting Fluids
WARNING!STARTING FLUIDS or flammable liquids are
NEVER TO BE USED in the Cummins Diesel (see
Warning label). Never pour diesel fuel, flammable
liquid, starting fluids (ether) into the air cleaner
canister, air intake piping, or turbocharger inlet in an
attempt to start the vehicle. This could result in a
flash fire and explosion causing serious personal
injury and engine damage.
The engine is equipped with an automatic electric air
preheating system. If the instructions in this manual are
followed, the engine should start in all conditions. WARNING!Do not leave children or animals inside parked
vehicles in hot weather. Interior heat build up may
cause serious injury or death.
NORMAL OPERATION – DIESEL ENGINE
Observe the following when the engine is operating.
• All message center lights are off.
• Check Engine Lamp is off.
• Engine Oil Pressure is above 10 psi (69 kPa) at idle.
• Low Oil Pressure light is off.
• Voltmeter Operation:
• The voltmeter may show a gauge fluctuation if
certain engine temperatures are below 66°F (19°C).
This cycling operation is caused by the post-heat STARTING AND OPERATING 257
5