2012 JEEP GRAND CHEROKEE temperature

DRIVE
This range should be used for most city and highway
driving. It provides the smoothest upshifts and down-
shifts, and the best fuel economy. The transmission
automatically upshifts through underdrive first and sec-
ond gears, direct third gear and overdrive fourth and
fifth gears. The DRIVE position provides optimum driv-
ing characteristics under all normal operating conditions.
To access all six available gears, you must use the
Electronic Range Select (ERS) feature (refer to “Electronic
Range Select (ERS)” in this section).
When frequent transmission shifting occurs (such as
when operating the vehicle under heavy loading condi-
tions, in hilly terrain, traveling into strong head winds, or
while towing heavy trailers), use the Electronic Range
Select (ERS) feature (refer to “Electronic Range Select
(ERS)” in this section) to select a lower gear range. Underthese conditions, using a lower gear range will improve
performance and extend transmission life by reducing
excessive shifting and heat buildup.
If the transmission operating temperature exceeds nor-
mal operating limits, the powertrain controller will
modify the transmission shift schedule and expand the
range of torque converter clutch engagement. This is
done to prevent transmission damage due to overheat-
ing.
If the transmission becomes extremely hot, the “Trans-
mission Temperature Warning Light” may illuminate and
the transmission may downshift out of Overdrive until
the transmission cools down.
NOTE:
Use caution when operating a heavily loaded
vehicle at low speeds (such as towing a trailer up a steep
grade, or in stop-and-go traffic) during hot weather. In
these conditions, torque converter slip can impose a
significant additional heat load on the cooling system.
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Downshifting the transmission to the lowest possible
gear (when climbing a grade), or shifting to NEUTRAL
(when stopped in heavy traffic) can help to reduce this
excess heat generation.
During cold temperatures, transmission operation may
be modified depending on engine and transmission
temperature as well as vehicle speed. This feature im-
proves warm up time of the engine and transmission to
achieve maximum efficiency. Engagement of both the
torque converter clutch and the top overdrive gear are
inhibited until the transmission fluid is warm (refer to the
“Note” under “Torque Converter Clutch” in this section).
During extremely cold temperatures (-16°F [-27°C] or
below), operation may briefly be limited to first and
direct gears only. Normal operation will resume once the
transmission temperature has risen to a suitable level.Transmission Limp Home Mode
Transmission function is monitored electronically for
abnormal conditions. If a condition is detected that could
result in transmission damage, Transmission Limp Home
Mode is activated. In this mode, the transmission remains
in third gear regardless of which forward gear is selected.
PARK, REVERSE, and NEUTRAL will continue to oper-
ate. The Malfunction Indicator Light (MIL) may be illu-
minated. Limp Home Mode allows the vehicle to be
driven to an authorized dealer for service without dam-
aging the transmission.
In the event of a momentary problem, the transmission
can be reset to regain all forward gears by performing the
following steps:
1. Stop the vehicle.
2. Shift the transmission into PARK.
3. Turn the ignition switch to the LOCK/OFF position.
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gear as the top available gear. Once in ERS mode, tapping
the shift lever to the left (-) or right (+) will change the top
available gear.
To exit ERS mode, simply press and hold the shift lever to
the right (+) until “D” is once again displayed in the shift
lever position indicator in the instrument cluster.
WARNING!
Do not downshift for additional engine braking on a
slippery surface. The drive wheels could lose their
grip and the vehicle could skid, causing an accident
or personal injury.
Screen
Display123456D
Actual Gear(s)
Allowed 1 1-2 1-3 1,2,4 1,2,
4,51,2,
4-6 1-5 NOTE:
To select the proper gear position for maximum
deceleration (engine braking), simply press and hold the
shift lever to the left (-). The transmission will shift to the
range from which the vehicle can best be slowed down.
Overdrive Operation
The automatic transmission includes an electronically
controlled Overdrive (fourth and fifth gears). The trans-
mission will automatically shift into the Overdrive gear if
the following conditions are present:
•the shift lever is in the DRIVE position,
•the transmission fluid has reached an adequate tem-
perature,
•the engine coolant has reached an adequate temperature,
•vehicle speed is sufficiently high,
•the driver is not heavily pressing the accelerator, and
•the TOW/HAUL switch has not been activated.
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Shifting Procedures
4WDHITo4WDLOW
With the vehicle at speeds of 0 to 3 mph (0 to 5 km/h), the
ignition switch in the ON position or the engine running,
shift the transmission into NEUTRAL, and press the
“4WD LOW” button once on the transfer case switch. The
“4WD LOW” indicator light in the instrument cluster
will begin to flash and remain on solid when the shift is
complete.NOTE:
If shift conditions/interlocks are not met, or a
transfer case motor temperature protection condition ex-
ists, a “For 4x4 Low Slow Below 3 MPH or 5 KPH Put
Trans in N Press 4 Low” message will flash from the
Electronic Vehicle Information Center (EVIC). Refer to
“Electronic Vehicle Information Center (EVIC)” in “Under-
standing Your Instrument Panel” for further information.
Transfer Case Switch
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4WD LOW To 4WD HI
With the vehicle at speeds of 0 to 3 mph (0 to 5 km/h), the
ignition switch in the ON position or the engine running,
shift the transmission into NEUTRAL, and press the
“4WD LOW” button once on the transfer case switch. The
“4WD LOW” indicator light in the instrument cluster
will flash and go out when the shift is complete.
NOTE:
•If shift conditions/interlocks are not met, or a transfer
case motor temperature protection condition exists, a
“For 4x4 High Slow Below 3 MPH or 5 KPH Put Trans
in N Press 4 Low” message will flash from the
Electronic Vehicle Information Center (EVIC). Refer to
“Electronic Vehicle Information Center (EVIC)” in
“Understanding Your Instrument Panel” for further
information.
•Shifting into or out of 4WD LOW is possible with the
vehicle completely stopped; however, difficulty mayoccur due to the mating clutch teeth not being prop-
erly aligned. Several attempts may be required for
clutch teeth alignment and shift completion to occur.
The preferred method is with the vehicle rolling 0 to
3 mph (0 to 5 km/h). If the vehicle is moving faster
than 3 mph (5 km/h), the transfer case will not allow
the shift.
NEUTRAL Shift Procedure
1. Turn the ignition switch to the ON position, engine off.
2. Vehicle stopped, with foot on brake.
3. Place the transmission into NEUTRAL.
4. Hold down the NEUTRAL “pin” switch (with a pen,
etc.) for four seconds until the LED light by the switch
starts to blink indicating shift in progress. The light will
stop blinking (stay on solid) when the NEUTRAL shift is
complete.
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occurred, which caused an over temperature condition in
the power steering system. You will lose power steering
assistance momentarily until the over temperature con-
dition no longer exists. Once driving conditions are safe,
then pull over and let vehicle idle for a few moments
until the light turns off. Refer to “Electronic Vehicle
Information Center (EVIC)” in “Understanding Your
Instrument Panel” for further information.
NOTE:
•Even if power steering assistance is no longer opera-
tional, it is still possible to steer the vehicle. Under
these conditions there will be a substantial increase in
steering effort, especially at very low vehicle speeds
and during parking maneuvers.
•If the condition persists, see your authorized dealer for
service.
5.7L Engine
The standard power steering system will give you good
vehicle response and increased ease of maneuverability
in tight spaces. The system will provide mechanical
steering capability if power assist is lost.
If for some reason the power assist is interrupted, it will
still be possible to steer your vehicle. Under these condi-
tions, you will observe a substantial increase in steering
effort, especially at very low vehicle speeds and during
parking maneuvers.
NOTE:
•Increased noise levels at the end of the steering wheel
travel are considered normal and do not indicate that
there is a problem with the power steering system.
•Upon initial start-up in cold weather, the power steer-
ing pump may make noise for a short amount of time.
This is due to the cold, thick fluid in the steering
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system. This noise should be considered normal, and it
does not in any way damage the steering system.
WARNING!
Continued operation with reduced power steering
assist could pose a safety risk to yourself and others.
Service should be obtained as soon as possible.
CAUTION!
Prolonged operation of the steering system at the end
of the steering wheel travel will increase the steering
fluid temperature and it should be avoided when
possible. Damage to the power steering pump may
occur.
Power Steering Fluid Check
Checking the power steering fluid level at a defined
service interval is not required. The fluid should only bechecked if a leak is suspected, abnormal noises are
apparent, and/or the system is not functioning as antici-
pated. Coordinate inspection efforts through an autho-
rized dealer.
CAUTION!
Do not use chemical flushes in your power steering
system as the chemicals can damage your power
steering components. Such damage is not covered by
the New Vehicle Limited Warranty.
WARNING!
Fluid level should be checked on a level surface and
with the engine off to prevent injury from moving
parts and to ensure accurate fluid level reading. Do
not overfill. Use only manufacturer’s recommended
power steering fluid.
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NOTE:
•The “ESC Activation/Malfunction Indicator Light”
and the “ESC OFF Indicator Light” come on momen-
tarily each time the ignition switch is turned ON.
•Each time the ignition is turned ON, the ESC system
will be ON even if it was turned off previously.
•The ESC system will make buzzing or clicking sounds
when it is active. This is normal; the sounds will stop
when ESC becomes inactive following the maneuver
that caused the ESC activation.The “ESC OFF Indicator Light” indicates the
Electronic Stability Control (ESC) is off.
TIRE SAFETY INFORMATION
Tire Markings
1 — U.S. DOT Safety
Standards Code (TIN) 4 — Maximum Load
2 — Size Designation 5 — Maximum Pressure
3 — Service Description 6 — Treadwear, Traction and Temperature Grades
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