2006 JEEP GRAND CHEROKEE ECU

WARNING!
Unintended movement of a vehicle could injure
those in and near the vehicle. As with all vehicles,
you should never exit a vehicle while the engine is
running. Before exiting a vehicle, you should apply
the park brake, shift the transmission into P (Park),
and remove the key from the ignition. Once the key
is removed from the ignition the transmission shift
lever is locked in the P (Park) position, securing the
vehicle against unwanted movement. Furthermore,
you should never leave children unattended inside a
vehicle.
R (Reverse)
Shift into this range only after the vehicle has come to a
complete stop.
N (Neutral)
No power is transmitted from the engine to the drive
axle. When the brakes are released, the vehicle can roll
freely. Do not engage in N (Neutral) position while
driving except to coast when the vehicle is in danger of
skidding (e.g., on icy roads).
NOTE:Towing the vehicle, coasting, or driving for any
other reason with selector lever in N (Neutral) can result
in severe transmission damage. Refer to“Recreational
Towing”in Section 5 and“Towing a Disabled Vehicle”in
Section 6 of this manual.
D (Drive)
The transmission automatically upshifts through fifth
gear. The D (Drive) position provides optimum driving
characteristics under all normal operating conditions.
Electronic Range Select (ERS)Operation
The Electronic Range Select (ERS) shift control allows
you to move the shifter left (-) or right (+) when the
256 STARTING AND OPERATING

WARNING!
Improper towing can lead to an injury accident.
Follow these guidelines to make your trailer towing
as safe as possible:
Make certain that the load is secured in the trailer
and will not shift during travel. When trailering
cargo that is not fully secured, dynamic load shifts
can occur that may be difficult for the driver to
control. You could lose control of your vehicle and
have an accident.
•When hauling cargo or towing a trailer, do not over-
load your vehicle or trailer. Overloading can cause a
loss of control, poor performance or damage to brakes,
axle, engine, transmission, steering, suspension, chas-
sis structure or tires.
•Safety chains must always be used between your
vehicle and trailer. Always connect the chains to the
frame or hook retainers of the vehicle hitch. Cross the
chains under the trailer tongue and allow enough
slack for turning corners.
•Vehicles with trailers should not be parked on a grade.
When parking, apply the parking brake on the tow
vehicle. Put the tow vehicle automatic transmission in
P for Park. With a manual transmission, shift the
transmission into reverse. And with four-wheel-drive
vehicles, make sure the transfer case is not in neutral.
Always, block orchockthe trailer wheels.
•GCWR must not be exceeded.
•Total weight must be distributed between the tow
vehicle and the trailer such that the following four
ratings are not exceeded:
1. GVWR
STARTING AND OPERATING 315
5

WARNING!
Raising the vehicle higher than necessary can make
the vehicle less stable. It could slip off the jack and
hurt someone near it. Raise the vehicle only enough
to remove the tire.
6. Remove the lug nuts and wheel.
7. Position the spare wheel/tire on the vehicle and install
the lug nuts with the cone-shaped end toward the wheel.
Lightly tighten the nuts. To avoid the risk of forcing the
vehicle off the jack, do not tighten the nuts fully until the
vehicle has been lowered.
8. Lower the vehicle by turning the jack screw counter
clockwise, and remove the jack and wheel blocks.9. Finish tightening the lug nuts. Push down on the
wrench while tightening for increased leverage. Alternate
nuts until each nut has been tightened twice. Correct
wheel nut tightness is 130 N·m (95 ft. lbs). If in doubt
about the correct tightness, have them checked with a
torque wrench by your authorized dealer or at a service
station.
10. Lower the jack to it’s fully closed position.
WARNING!
A loose tire or jack, thrown forward in a collision or
hard stop could endanger the occupants of the ve-
hicle. Always stow the jack parts and the spare tire in
the places provided.
11. Secure the tire, jack, and tools in their proper loca-
tions.
WHAT TO DO IN EMERGENCIES 335
6

5. Connect the other cable, first to the negative terminal
of the booster battery and then connect the other end to
a non-paint metal surface on the engine of the vehicle
with the discharged battery. Make sure you have a good
contact on the engine.
6. Start the engine in the vehicle which has the booster
battery, let the engine idle a few minutes, then start the
engine in the vehicle with the discharged battery.
7. When removing the jumper cables, reverse the above
sequence exactly. Be careful of the moving belts and fan.
NOTE:To start the vehicle following connection of a
booster battery, the Security Alarm System must first be
disabled by cycling a front door key cylinder or by using
the keyless entry transmitter.WARNING!
Jump starting can be dangerous. To avoid personal
injury or damage to electrical components in vehicle,
observe the following warnings:
•Battery fluid is a corrosive acid solution and can burn
or even blind you. Don’t allow battery fluid to contact
your eyes, skin, or clothing. Don’t lean over a battery
when attaching clamps. If acid splashes in eyes or on
skin, flush the area immediately with large amounts of
water.
•Do not use a booster battery or any other booster
source that has a greater than 12–volt system, i.e., do
not use a 24–volt power source.
•Never attempt to jump start a discharged battery that
is frozen, because it could rupture or explode during
jump starting.
WHAT TO DO IN EMERGENCIES 337
6

ONLY the correct type thermostat. Other designs may
result in unsatisfactory cooling performance, poor gas
mileage, and increased emissions.
Hoses and Vacuum/Vapor Harnesses
Inspect surfaces of hoses and nylon tubing for evidence
of heat and mechanical damage. Hard or soft spots,
brittle rubber, cracking, tears, cuts, abrasions, and exces-
sive swelling indicate deterioration of the rubber.
Pay particular attention to the hoses nearest to high heat
sources such as the exhaust manifold. Inspect hose rout-
ing to be sure hoses do not touch any heat source or
moving component that may cause heat damage or
mechanical wear.
Insure nylon tubing in these areas has not melted or
collapsed. Inspect all hose connections such as clamps
and couplings to make sure they are secure and no leaksare present. Components should be replaced immedi-
ately if there is any evidence of degradation that could
cause failure.
Brake System
In order to assure brake system performance, all brake
system components should be inspected periodically.
Refer to the appropriate“Maintenance Schedule”in
Section 8 for suggested service intervals.
WARNING!
Riding the brakes can lead to brake failure and
possibly an accident. Driving with your foot resting
or riding on the brake pedal can result in abnormally
high brake temperatures, excessive lining wear, and
possible brake damage. You wouldn’t have your full
braking capacity in an emergency.
MAINTAINING YOUR VEHICLE 369
7

Brake and Power Steering System Hoses
When servicing the vehicle for scheduled maintenance,
inspect surface of hoses for evidence of heat and me-
chanical damage. Hard and brittle rubber, cracking, tears,
cuts, abrasion, and excessive swelling suggest deteriora-
tion of the rubber. Particular attention should be made to
examining those hose surfaces nearest to high heat
sources, such as the exhaust manifold.
Inspect all hose clamps and couplings to make sure they
are secure and no leaks are present.
NOTE:Often fluids such as oil, power steering fluid,
and brake fluid are used during assembly plant opera-
tions to ease the assembly of hoses to couplings. There-
fore, oil wetness at the hose-coupling area is not neces-
sarily an indication of leakage. Actual dripping of hot
fluid when systems are under pressure (during vehicle
operation) should be noted before hose is replaced based
on leakage.NOTE:Inspection of brake hoses should be done when-
ever the brake system is serviced and every engine oil
change.
WARNING!
Worn brake hoses can burst and cause brake failure.
You could have an accident. If you see any signs of
cracking, scuffing, or worn spots, have the brake
hoses replaced immediately.
Brake Master Cylinder
The fluid level in the master cylinder should be checked
when performing under hood services, or immediately if
the brake system warning lamp shows system failure
370 MAINTAINING YOUR VEHICLE

4. Pull the bulb to remove it from the socket.
5. Replace the bulb, reinstall the socket, and reattach the
light assembly.
Center High Mounted Stop Light (CHMSL)
1. Remove the two screws securing the CHMSL.
2. Twist the bulb socket to remove from the CHMSL
housing.
3. Pull the bulb out of the socket.
4. Replace the bulb, reinstall the socket and reattach the
CHMSL.
MAINTAINING YOUR VEHICLE 391
7

ABS (Anti-Lock Brake System)............181,269
Adding Washer Fluid..................... 171
Adjustable Pedals....................... 146
Air Cleaner, Engine (Engine Air Cleaner Filter) . . . 358
Air Conditioner Maintenance............... 359
Air Conditioning........................ 233
Air Conditioning, Operating Tips............ 237
Air Conditioning Refrigerant............... 360
Air Conditioning System.................. 233
Air Filter.............................. 358
Air Pressure, Tires....................... 288
Airbag................................ 41
Airbag Deployment....................... 53
Airbag Light.......................56,70,181
Airbag Maintenance....................... 55
Alarm (Security Alarm).................24,182
Alarm System (Security Alarm)............... 24
Alignment and Balance................... 293
Alterations/Modifications, Vehicle............. 8Antenna, Satellite Radio................... 230
Antifreeze (Engine Coolant)................ 392
Anti-Lock Brake System (ABS)............131,269
Anti-Lock Warning Light.................. 181
Anti-Theft System.....................24,182
Appearance Care........................ 376
Auto Down Power Windows................ 29
Automatic Dimming Mirror................. 79
Automatic Door Locks..................... 19
Automatic Headlights.................... 122
Automatic Temperature Control (ATC)......... 238
Automatic Transmission................254,371
Adding Fluid......................... 373
Fluid and Filter Changes................. 371
Fluid Level Check...................... 372
Fluid Type........................... 371
Special Additives...................... 374
Torque Converter...................... 260
Autostick............................. 256
424 INDEX