2007 JEEP GRAND CHEROKEE check engine

WARNING!
Exhaust gases can injure or kill. They contain carbon
monoxide (CO) which is colorless and odorless.
Breathing it can make you unconscious and can
eventually poison you. To avoid breathing CO, refer
to Exhaust Gas in the Safety Tips section of this
manual.
Cooling System
WARNING!
You or others can be badly burned by hot antifreeze/
coolant or steam from your radiator. If you see or
hear steam coming from under the hood, don’t open
the hood until the radiator has had time to cool.
Never try to open a cooling system pressure cap
when the radiator or coolant bottle is hot.
Engine Coolant Checks
Check antifreeze/coolant protection every 12 months
(before the onset of freezing weather, where applicable).
If antifreeze/coolant is dirty or rusty in appearance, the
system should be drained, flushed and refilled with fresh
antifreeze/coolant. Check the front of the A/C condenser
376 MAINTAINING YOUR VEHICLE

for any accumulation of bugs, leaves, etc. If dirty, clean by
gently spraying water from a garden hose vertically
down the face of the condenser.
Check the engine cooling system hoses for brittle rubber,
cracking, tears, cuts, and tightness of the connection at
the coolant recovery bottle and radiator. Inspect the
entire system for leaks.
With the engine at normal operating temperature (but
not running), check the cooling system pressure cap for
proper vacuum sealing by draining a small amount of
coolant from the radiator drain cock. If the cap is sealing
properly, the antifreeze/coolant will begin to drain from
the coolant recovery bottle. DO NOT REMOVE THE
COOLANT PRESSURE CAP WHEN THE COOLING
SYSTEM IS HOT.Cooling System — Drain, Flush, And Refill
At the intervals shown in the appropriate “Maintenance
Schedule,” the system should be drained, flushed, and
refilled.
If the solution is dirty and contains a considerable
amount of sediment, clean and flush with reliable cooling
system cleaner. Follow with a thorough rinsing to remove
all deposits and chemicals. Properly dispose of old
antifreeze/coolant solution.
Selection Of Coolant
Use only the manufacturer’s recommended antifreeze/
coolant, refer to Fluids, Lubricants, and Genuine Parts for
correct antifreeze/coolant type.
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Disposal of Used Engine Coolant
Used ethylene glycol-based antifreeze/coolant is a regu-
lated substance requiring proper disposal. Check with
your local authorities to determine the disposal rules for
your community. To prevent ingestion by animals and
children, do not store ethylene glycol-based antifreeze/
coolant in open containers or allow it to remain in
puddles on the ground. If ingested by a child, contact a
physician immediately. Clean up any ground spills im-
mediately.
Coolant Level
The coolant bottle provides a quick visual method for
determining that the antifreeze/coolant level is adequate.
With the engine idling, and warm to normal operating
temperature, the level of the antifreeze/coolant in the
bottle should be between the ranges indicated on the
bottle.The radiator normally remains completely full, so there is
not need to remove the radiator cap unless checking for
antifreeze/coolant freeze point or replacing antifreeze/
coolant. Advise your service attendant of this. As long as
the engine operating temperature is satisfactory, the
coolant bottle need only be checked once a month.
When additional antifreeze/coolant is needed to main-
tain the proper level, it should be added to the coolant
bottle. Do not overfill.
Points To Remember
NOTE:When the vehicle is stopped after a few miles
(kilometers) of operation, you may observe vapor coming
from the front of the engine compartment. This is nor-
mally a result of moisture from rain, snow, or high
humidity accumulating on the radiator and being vapor-
ized when the thermostat opens, allowing hot antifreeze/
coolant to enter the radiator.
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If an examination of your engine compartment shows no
evidence of radiator or hose leaks, the vehicle may be
safely driven. The vapor will soon dissipate.
•Do not overfill the coolant recovery bottle.
•Check antifreeze/coolant freeze point in the radiator
and in the coolant recovery bottle. If antifreeze/
coolant needs to be added, contents of coolant recov-
ery bottle must also be protected against freezing.
•If frequent antifreeze/coolant additions are required,
or if the level in the coolant recovery bottle does not
drop when the engine cools, the cooling system should
be pressure tested for leaks.
•Maintain antifreeze/coolant concentration at 50%
HOAT antifreeze/coolant (minimum) and distilled
water for proper corrosion protection of your engine
which contains aluminum components.
•Make sure that the radiator and coolant recovery
bottle hoses are not kinked or obstructed.
•Keep the front of the radiator clean. If your vehicle is
equipped with air conditioning, keep the front of the
condenser clean, also.
•Do not change the thermostat for summer or winter
operation. If replacement is ever necessary, install
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.
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Brake Master Cylinder — Brake Fluid Level Check
The fluid level of the master cylinder should be checked
when performing under the hood service, or immedi-
ately if the brake system warning lamp indicates system
failure.
The brake master cylinder has a translucent plastic
reservoir. On the outboard side of the reservoir, there is a
“MAX” dot and an “MIN” dot. The fluid level must be
kept within these two dots. Do not add fluid above the
MAX mark, because leakage may occur at the cap.
With disc brakes the fluid level can be expected to fall as
the brake linings wear. However, an unexpected drop in
fluid level may be caused by a leak and a system check
should be conducted.
Refer to Fluids, Lubricants and Genuine Parts for the
correct fluid type.WARNING!
Use of a brake fluid that may have a lower initial
boiling point, or is unidentified as to specification,
may result in sudden brake failure during hard
prolonged braking. You could have an accident.
WARNING!
Overfilling the brake fluid reservoir can result in
spilling brake fluid on hot engine parts and the
brake fluid catching fire.
Use only brake fluid that has been in a tightly closed
container to avoid contamination from foreign matter or
moisture.
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Check the fluid level while the transmission is at normal
operating temperature. This occurs after at least 15 miles
(25 km) of driving. At normal operating temperature the
fluid cannot be held comfortably between the fingertips.
To check the automatic transmission fluid level properly,
the following procedure must be used:
1. Operate the engine at idle speed and normal operating
temperature.
2. The vehicle must be on level ground.
3. Fully apply the parking brake and press the brake
pedal.
4. Place the gear selector momentarily in each gear
position ending with the lever in P (Park).
5. Remove the dipstick, wipe it clean and reinsert it until
seated.6. Remove the dipstick again and note the fluid level on
both sides. The fluid level should be between the “HOT”
(upper) reference holes on the dipstick at normal operat-
ing temperature. The fluid level is only valid if there is a
solid coating of oil is seen on both sides of the dipstick. If
the fluid is low, add as required into the dipstick tube.Do
not overfill.After adding any quantity of oil through the
oil fill tube, wait a minimum of two (2) minutes for the oil
to fully drain into the transmission before rechecking the
fluid level.
NOTE:If it is necessary to check the transmissionbelow
the operating temperature, the fluid level should be
between the two “COLD” (lower) holes on the dipstick
with the fluid at approximately 70°F (21°C) (room tem-
perature). If the fluid level is correctly established at
room temperature, it should be between the “HOT”
(upper) reference holes when the transmission reaches
180°F (82°C). Remember it is best to check the level at the
normal operating temperature.
MAINTAINING YOUR VEHICLE 387
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•Taxi, police, or delivery service (commercial service)
•Off-road or desert driving
NOTE:Most vehicles are operated under the conditions
listed for Schedule “B.”
NOTE:IfANYof these apply to you, change your
engine oil every 3,000 miles (5 000 km) or 3 months,
whichever comes first, and follow the maintenance rec-
ommendations in “Maintenance Schedule B.”
NOTE:IfANYof these apply to you then flush and
replace your engine coolant every 102,000 miles (170 000
km) or 60 months, whichever comes first, and follow
“Schedule B” of the “Maintenance Schedules” section of
this manual.
Second is Schedule“A”. It is for vehicles that are not
operated under any of the conditions listed under Sched-
ule “B.”Use the schedule that best describes your driving condi-
tions. Where time and mileage are listed, follow the
interval that occurs first.
CAUTION!
Failure to perform the required maintenance items
may result in damage to the vehicle.
At Each Stop for Fuel
•Check the engine oil level about 5 minutes after a fully
warmed engine is shut off. Checking the oil level while
the vehicle is on level ground will improve the accu-
racy of the oil level reading. Add oil only when the
level is at or below the ADD or MIN mark.
•Check the windshield washer solvent, add as required.
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Once a Month
•Check the tire pressure and look for unusual wear or
damage.
•Inspect the battery and clean and tighten the terminals
as required.
•Check the fluid levels of the coolant reservoir, brake
master cylinder, and transmission, and add as needed.
•Check all lights and all other electrical items for correct
operation.At Each Oil Change
•Change the engine oil filter.
•Inspect the exhaust system.
•Inspect brake hoses.
•Check the engine coolant/anti-freeze level, hoses, and
clamps.
•After completion of off-road operation, the underside
of the vehicle should be thoroughly inspected. Exam-
ine threaded fasteners for looseness.
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