2005 JEEP GRAND CHEROKEE ECU

•Make certain that the load is secured in the trailer and
will not shift during travel.
•It is recommended thatanyhitches installed on your
vehicle be factory installed, or installed by a dealer
using factory approved parts. Factory approved parts
are specifically engineered with your vehicle’s perfor-
mance in mind, including the possibility that it will be
involved in an accident. Other hitches may not have
been so engineered. Vehicle performance, including
vehicle damage in an accident situation, may therefore
be different.
•If trailer towing is required and your vehicle is not
equipped with a trailer tow package, the Mopar
accessory towing harnesses are the only approved
method to provide for trailer lights. These harnesses
are designed to provide current to the trailer lights but
bypass the module designed to monitor tail lights.
Refer to the package instructions for details.
Trailer and Tongue Weight
Gross Trailer Weight (GTW) means the weight of the
trailer plus the weight of all cargo, consumables and
equipment loaded on the trailer when in actual under-
way towing condition. The best way to measure GTW is
to put your fully loaded trailer on a vehicle scale. The
entire weight of the trailer must be supported by the
scale.
Always load a trailer with 60% of the cargo weight in the
front of the trailer. This places approximately 10% to 15%
of the GTW on the tow hitch of your vehicle. This portion
of the GTW becomes the tongue weight.
Trailer sway control and equalizing hitch are required for
tongue weights above 350 lbs (159 kg)., i.e., trailer
weights heavier than 3,500 lbs (1 587 kg).
STARTING AND OPERATING 285
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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.
NOTE:Tire should be stowed with the “beauty” side
up. Storing the tire upside down may result in scratchingor damage to the wheel face. Continue winching up the
tire until you hear the winch “ratchet” three times.
Double check to ensure the tire is snug against the
underbody of the vehicle. Damage to the winch cable
may result if the vehicle is driven with the tire loose.
12. Reinstall the rubber plug into the floor of the cargo
area.
JUMP STARTING PROCEDURE
NOTE:Check the test indicator on top of battery for
battery fluid level. If the indicator is clear, the level is low.
Add water to the proper level and reinstall the vent caps
before attempting to jump start the vehicle.
1. Wear eye protection and remove any metal jewelry
such as watch bands or bracelets that might make an
unintended electrical contact.
2. When boost is provided by a battery in another
vehicle, park that vehicle within booster cable reach but
WHAT TO DO IN EMERGENCIES 303
6

without letting the vehicles touch. Set the parking brake,
place the transmission in P (Park), and turn the ignition
to OFF for both vehicles.
3. Turn off the heater, radio and all unnecessary electrical
loads.
4. Connect one end of a jumper cable to the positive
terminal of the discharged battery. Connect the other end
of the same cable to the positive terminal of the booster
battery.
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
304 WHAT TO DO IN EMERGENCIES

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.
334 MAINTAINING YOUR VEHICLE

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
Be sure to clean the top of the master cylinder area before
removing the cap. If necessary, add fluid to bring the
fluid level up to the requirements described on the brake
MAINTAINING YOUR VEHICLE 335
7

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.
356 MAINTAINING YOUR VEHICLE

Lumbar Support....................... 101
Memory............................. 106
Power.............................. 102
Rear Folding......................... 103
Reclining............................ 100
Security Against Theft..................... 15
Security Alarm (Theft Alarm).............22,166
Selection of Oil......................... 318
Sentry Key............................. 12
Sentry Key Programming................... 14
Sentry Key Replacement................... 13
Service Assistance....................... 384
Service Contract......................... 386
Service Engine Soon Light (Malfunction Indicator) . 164
Service Manuals........................ 389
Setting the Clock.....................188,202
Shifting
Automatic Transmission................. 233
Shoulder Belts........................... 28Signals, Turn................... 116,164,353,355
Snow Chains (Tire Chains)................. 275
Snow Plow............................ 293
Spare Tire............................. 299
Spark Plugs............................ 321
Specifications
Fuel................................ 277
Oil ................................ 318
Speed Control.......................... 134
Speedometer........................... 164
Starting............................... 230
Automatic Transmission................. 230
Cold Weather......................231,232
Emergency (Jump Starting)............... 303
Engine Block Heater.................... 232
Engine Fails to Start.................... 231
Steering
Power.............................. 326
Wheel, Tilt........................... 120
INDEX 405
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