2005 JEEP GRAND CHEROKEE ignition

4. As soon as you turn your key to the ON position, you
will see your MIL symbol come on as part of a normal
bulb check.
5. Approximately 15 seconds later, one of two things will
happen:
a. The MIL will flash for about 10 seconds and then
return to being fully illuminated until you turn off the
ignition key or start the engine. This means that your
vehicle’s OBD system isnot readyand you shouldnot
proceed to the I/M station.
b. The MIL will not flash at all and will remain fully
illuminated until you turn off the ignition key or start
the engine. This means that your vehicle’s OBD system
isreadyand you can proceed to the I/M station.
If your OBD system isnot ready,you should see your
authorized dealer or repair facility. If your vehicle was
recently serviced or had a battery failure or replacement,you may need to do nothing more than drive your
vehicle as you normally would in order for your OBD
system to update. A recheck with the above test routine
may then indicate that the system is now ready.
Regardless of whether your vehicle’s OBD system is
ready or not ready, if the MIL symbol is illuminated
during normal vehicle operation, you should have your
vehicle serviced before going to the I/M station. The I/M
station can fail your vehicle because the MIL symbol is on
with the engine running.
REPLACEMENT PARTS
Use of genuine Moparparts for normal/scheduled
maintenance and repairs is highly recommended to in-
sure the designed performance. Damage or failures
caused by the use of non-Moparparts for maintenance
and repairs will not be covered by the manufacturer’s
warranty.
MAINTAINING YOUR VEHICLE 315
7

WARNING!
A hot exhaust system can start a fire if you park over
materials that can burn. Such materials might be
grass or leaves coming into contact with your ex-
haust system. Do not park or operate your vehicle in
areas where your exhaust system can contact any-
thing that can burn.
In unusual situations involving grossly malfunctioning
engine operation, a scorching odor may suggest severe
and abnormal catalyst overheating. If this occurs, stop
the vehicle, turn off the engine and allow it to cool.
Service, including a tune up to manufacturer’s specifica-
tions, should be obtained immediately.
To minimize the possibility of catalytic converter dam-
age:
•Do not shut off the engine or interrupt the ignition
when the transmission is in gear and the vehicle is in
motion.
•Do not try to start the engine by pushing or towing the
vehicle.
•Do not idle the engine with any spark plug wires
disconnected or removed, such as when diagnostic
testing.
•Do not idle the engine for prolonged periods during
very rough idle or malfunctioning operating condi-
tions.
•Do not allow vehicle to run out of fuel.
NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
322 MAINTAINING YOUR VEHICLE

Ignition Cables
Replace the ignition cables (5.7L engines only) at the
mileage interval shown in the maintenance charts.
Crankcase Emission Control System
Proper operation of this system depends on freedom
from sticking or plugging due to deposits. As vehicle
mileage builds up, the PCV valve and passages may
accumulate deposits. If a valve is not working properly,
replace it with a new valve. DO NOT ATTEMPT TO
CLEAN THE OLD PCV VALVE!
Check ventilation hose for indication of damage or
plugging deposits. Replace if necessary.
Fuel Filter
A plugged fuel filter can cause hard starting or limit the
speed at which a vehicle can be driven. Should an
excessive amount of dirt accumulate in the fuel tank,
frequent replacement of the fuel filter which is mounted
in the fuel tank may be necessary.
Air Cleaner Filter
Under normal driving conditions, replace the air filter at
the intervals shown on “Maintenance Schedule A.” If,
however, you drive the vehicle frequently under dusty or
severe conditions, the filter element should be inspected
periodically and replaced if necessary at the intervals
shown on “Maintenance Schedule B.”
WARNING!
The air cleaner can provide protection in the case of
engine backfire. Do not remove the air cleaner
unless it is necessary for repair or maintenance.
Make sure that no one is near the engine compart-
ment before starting the vehicle with the air cleaner
removed. Failure to do so can result in serious
personal injury.
MAINTAINING YOUR VEHICLE 323
7

VEHICLE STORAGE
If you are leaving your vehicle dormant for more than 21
days you may want to take steps to protect your battery.
You may:
•Remove fuse #27 in the Intelligent Power Module
labeled Ignition-Off Draw (IOD#1).
•Or, disconnect the negative cable from the battery.
•Anytime you store your vehicle, or keep it out of
service (i.e. vacation) for two weeks or more, run the
air conditioning system at idle for about five minutes
in the fresh air and high blower setting. This will
insure adequate system lubrication to minimize the
possibility of compressor damage when the system is
started again.
REPLACEMENT BULBS
Interior Lights Bulb Type
Glove Box Light......................... 194
Grab Handle Light................L002825W5W
Overhead Console Reading Lights..........VT4976
Rear Cargo Light.......................214–2
Visor Vanity Light.....................V26377
Underpanel Courtesy Lights................. 906
Instrument Cluster (General Illumination)....... 103
Telltale/Hazard Light...................... 74
* Available only from authorized dealers.
Exterior Lights Bulb Type
Backup Lights.........................3157A
Fog Lights.............................9145
Front Park Lights (Limited)...............194NA
Front Park Lights (Laredo)................194NA
Front Park/Turn Light (Limited)............3157A
350 MAINTAINING YOUR VEHICLE

Miles 48,000 51,000 54,000 57,000 60,000
(Kilometers) (77 000) (82 000) (86 000) (91 000) (96 000)
Change the engine oil and engine oil filter, if not
replaced at 3 months.X X XXX
Rotate the tires. X X X
Inspect the engine air cleaner filter, replace if nec-
essary.X
Inspect the PCV Valve, replace if necessary. X
Replace the spark plugs.X
Inspect the ignition cables, replace if necessary
(5.7L Only).X
Inspect drive belt, replace if necessary. X
Lubricate the upper knuckle ball stud at steering &
suspension ball joints.XXX
Inspect the brake linings. X X
SCHEDULE “B” 369
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Miles 108,000 111,000 114,000 117,000 120,000
(Kilometers) (173 000) (178 000) (182 000) (187 000) (192 000)
Change the engine oil and engine oil filter, if not
replaced at 3 months.X X XXX
Rotate the tires. X X X
Inspect the engine air cleaner filter, replace if nec-
essary.X
Inspect the PCV Valve, replace if necessary. X
Replace the spark plugs.X
Inspect the ignition cables, replace if necessary
(5.7L Only).X
Inspect the drive belt, replace if necessary. X
Lubricate the upper knuckle ball stud at steering &
suspension ball joints.XXX
Inspect the brake linings. X X
Drain and refill the front and rear axle fluid. X X
374 SCHEDULE “B”
8
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Miles 60,000 66,000 72,000 78,000
(Kilometers) (96 000) (106 000) (115 000) (125 000)
[Months] [60] [66] [72] [78]
Change the engine oil and engine oil filter. X X X X
Rotate the tires. X X X X
Inspect the engine air cleaner filter, and replace if nec-
essary.X
Inspect the PCV Valve, replace if necessary. X
Replace the spark plugs.X
Inspect the ignition cables, replace if necessary (5.7L
Only).X
Inspect the drive belt, replace if necessary. X
Lubricate the upper knuckle ball stud at steering & sus-
pension ball joints.XX
Flush and replace the engine coolant/anti-freeze, at 60
months if not done at 102,000 miles (163 000 km).X
Inspect the brake linings. X
Drain the transfer case and refill. X
378 SCHEDULE “A”
8
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Miles 108,000 114,000 120,000
(Kilometers) (173 000) (182 000) (192 000)
[Months] [108] [114] [120]
Change the engine oil and engine oil filter. X X X
Rotate the tires. X X X
Inspect the engine air cleaner filter, and replace if necessary.X
Inspect the PCV Valve, replace if necessary. X
Replace the spark plugs.X
Inspect the ignition cables, replace if necessary (5.7L Only).X
Inspect the drive belt, replace if necessary. X
Lubricate the upper knuckle ball stud at steering & suspension
ball joints.XX
Inspect the brake linings. X
Flush and replace the engine coolant/anti-freeze if not done at
102,000 miles (163 000 km).X
Drain the transfer case and refill.X
380 SCHEDULE “A”
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