wheel DODGE RAM 2500 DIESEL 2009 4.G Repair Manual

If either the front or rear hydraulic system loses normal
braking capability, the remaining system will still func-
tion with some loss of overall braking effectiveness. This
will be evident by increased pedal travel during applica-
tion, greater pedal force required to slow or stop, and
activation of the “Brake Warning Light” and the “ABS
Warning Light” (If Equipped) during brake use.3500 Dual Rear Wheel Models OnlyThe brake system power assist is provided by a hydro-
boost unit which shares fluid with the power steering
system. You may experience some clicking or hissing
noises from the hydro-boost system during hard braking
conditions.
NOTE:Under cold temperatures, pedal effort will be
higher than normal until the power steering fluid reaches
operating temperature.
Four-Wheel Anti-Lock Brake System
WARNING!
The Four-Wheel Anti-Lock Brake System contains
sophisticated electronic equipment. It may be sus-
ceptible to interference caused by improperly in-
stalled or high output radio transmitting equipment.
This interference can cause possible loss of anti-lock
braking capability. Installation of such equipment
should be performed by qualified professionals.
The Four-Wheel Anti-lock Brake System (ABS) is de-
signed to aid the driver in maintaining vehicle control
under adverse braking conditions. The system operates
with a separate computer to modulate hydraulic pressure
to prevent wheel lockup and help avoid skidding on
slippery surfaces.
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WARNING! (Continued)
•
The Anti-Lock Brake System (ABS) cannot prevent
the natural laws of physics from acting on the
vehicle, nor can it increase braking or steering
efficiency beyond that afforded by the condition
of the vehicle brakes and tires or the traction
afforded.
•
The ABS cannot prevent accidents, including
those resulting from excessive speed in turns,
following another vehicle too closely, or hydro-
planing. Only a safe, attentive, and skillful driver
can prevent accidents.
•
The capabilities of an ABS-equipped vehicle must
never be exploited in a reckless or dangerous
manner which could jeopardize the user’s safety
or the safety of others.
ELECTRONIC BRAKE CONTROL SYSTEM — IF
EQUIPPEDYour vehicle is equipped with an advanced electronic
brake control system that includes Anti-Lock Brake Sys-
tem (ABS), Traction Control System (TCS), Brake Assist
System (BAS), HSA (Hill Start Assist), Electronic Roll
Mitigation (ERM), Electronic Stability Program (ESP) and
Trailer Sway Control (TSC). All six systems work to-
gether to enhance vehicle stability and control in various
driving conditions, and are commonly referred to as ESP.Anti-Lock Brake System (ABS)The ABS aids the driver in maintaining vehicle control
under adverse braking conditions. The system controls
hydraulic brake pressure to prevent wheel lockup and
help avoid skidding on slippery surfaces during braking.
For more information about ABS, refer to “Anti-Lock
Brake System” under “Brake System” in Section 5 of this
manual.
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NOTE:ABS improves steering control of the vehicle
during hard braking maneuvers.
WARNING!
•
ABS cannot prevent the natural laws of physics
from acting on the vehicle, nor can it increase
braking or steering efficiency beyond that af-
forded by the condition of the vehicle brakes and
tires or the traction afforded.
•
The ABS cannot prevent accidents, including
those resulting from excessive speed in turns,
following another vehicle too closely, or hydro-
planing. Only a safe, attentive, and skillful driver
can prevent accidents.
•
The capabilities of an ABS-equipped vehicle must
never be exploited in a reckless or dangerous
manner which could jeopardize the user’s safety
or the safety of others.
Traction Control System (TCS)The TCS monitors the amount of wheel spin of each of
the driven wheels. If wheel spin is detected, brake
pressure is applied to the slipping wheel(s), and engine
power is reduced to provide enhanced acceleration and
stability. A feature of the TCS functions similar to a
limited-slip differential and controls the wheel spin
across a driven axle. If one wheel on a driven axle is
spinning faster than the other, the system will apply the
brake of the spinning wheel. This will allow more engine
torque to be applied to the wheel that is not spinning.
This feature remains active even if TCS and ESP are in the
“Partial Off” mode. Refer to “Electronic Stability Pro-
gram (ESP)” in this section of this manual. This brake
pressure modulation transfers drive torque from slipping
to non-slipping wheels to provide optimal forward
traction.
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WARNING!
•
If you use a trailer brake controller with your
trailer, your trailer brakes may be activated and
deactivated with the brake switch. If so, when the
brake pedal is released, there may not be enough
brake pressure to hold the vehicle and trailer on a
hill and this could cause a collision with another
vehicle or object behind you. In order to avoid
rolling down the incline while resuming accelera-
tion, manually activate the trailer brake or apply
more vehicle brake pressure prior to releasing the
brake pedal. Always remember the driver is re-
sponsible for braking the vehicle.(Continued)
WARNING! (Continued)
•
HSA is not a parking brake. If you stop the vehicle
on a hill without putting the transmission in
PARK or using the parking brake, it will roll down
the incline and could cause a collision with an-
other vehicle or object. Always remember to use
the parking brake while parking on a hill, and that
the driver is responsible for braking the vehicle.
HSA OffIf you wish to turn off the HSA system, follow this
procedure:
1. Start with the engine off, and vehicle in PARK with
wheels straight.
2. Start the engine.
3. With the engine running, the brake applied, rotate the
steering wheel 180° counterclockwise from center.
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4. Press ESP button four times within twenty seconds.
The “ESP/TCS Indicator Light” should appear and dis-
appear four times.
5. Rotate the steering wheel 360° clockwise (180° clock-
wise from center).
6. Cycle ignition switch OFF then ON.
7. If the sequence was completed properly, the “ESP/
TCS Indicator Light” will blink several times to confirm
HSA is off.
Steps 1-7 must be completed within 90 seconds to turn off
HSA. Repeat steps 1-7 to re-enable HSA functionality.Electronic Roll Mitigation (ERM)The ERM system anticipates the potential for wheel lift
by monitoring the driver ’s steering wheel input and the
speed of the vehicle. When ERM determines that the rate
of change of the steering wheel angle and vehicle speed
are sufficient to potentially cause wheel lift, it applies theappropriate brake and may reduce engine power to
lessen the chance that wheel lift will occur. ERM will only
intervene during very severe or evasive driving maneu-
vers.
ERM can only reduce the chance of wheel lift occurring
during severe or evasive driving maneuvers. It cannot
prevent wheel lift due to other factors such as road
conditions, leaving the roadway or striking objects or
other vehicles.
WARNING!
Many factors, such as vehicle loading, road condi-
tions and driving conditions, influence the chance
that wheel lift or rollover may occur.
(Continued)
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WARNING! (Continued)
•
ERM cannot prevent all wheel lift or rollovers,
especially those that involve leaving the roadway
or striking objects or other vehicles. Only a safe,
attentive, and skillful driver can prevent accidents.
•
The capabilities of an ERM-equipped vehicle
must never be exploited in a reckless or dangerous
manner which could jeopardize the user’s safety
or the safety of others.
Electronic Stability Program (ESP)The ESP system enhances directional control and stability
of the vehicle under various driving conditions. ESP
corrects for oversteering or understeering of the vehicle
by applying the brake of the appropriate wheel to assist
in counteracting the oversteer or understeer condition.
Engine power may also be reduced to help the vehicle
maintain the desired path.ESP uses sensors in the vehicle to determine the vehicle
path intended by the driver and compares it to the actual
path of the vehicle. When the actual path does not match
the intended path, ESP applies the brake of the appropri-
ate wheel to assist in counteracting the oversteer or
understeer condition.
•
Oversteer - when the vehicle is turning more than
appropriate for the steering wheel position.
•
Understeer - when the vehicle is turning less than
appropriate for the steering wheel position.
ESP/TCS Indicator Light
The “ESP/TCS Indicator Light” located in the
instrument cluster, starts to flash as soon as the
tires lose traction and the ESP system becomes
active. The “ESP/TCS Indicator Light” also
flashes when TCS is active. If the “ESP/TCS Indicator
Light” begins to flash during acceleration, ease up on the
340 STARTING AND OPERATING

accelerator and apply as little throttle as possible. Be sure
to adapt your speed and driving to the prevailing road
conditions.
WARNING!
•
ESP (Electronic Stability Program) cannot prevent
the natural laws of physics from acting on the
vehicle, nor can it increase the traction afforded by
prevailing road conditions.
•
ESP cannot prevent accidents, including those
resulting from excessive speed in turns, driving on
slippery surfaces, or hydroplaning. Only a safe,
attentive, and skillful driver can prevent accidents.
•
The capabilities of an ESP-equipped vehicle must
never be exploited in a reckless or dangerous
manner which could jeopardize the user’s safety
or the safety of others.The ESP system has multiple operating modes depend-
ing on vehicle type: Two-Wheel Drive (2WD) or Four-
Wheel Drive (4WD). Four-wheel drive vehicles may be
equipped with either a four-mode position (2WD/4WD
LOCK/4WD LOW/Neutral) transfer case or a five-mode
position (2WD/4WD AUTO/4WD LOCK/4WD LOW/
Neutral) transfer case. If you have a four-wheel drive
vehicle, and want to determine which transfer case is on
your vehicle and how to operate it, refer to the “Four
Wheel Drive Operation” in this section.
All 2WD vehicles and 4WD vehicles in 2WD,
AUTO or 4HI Modes can choose the following ESP
operating modes:ESP On
This is the normal operating mode for ESP in 2WD/
AUTO/4HI Modes and in 2WD vehicles. Whenever the
vehicle is started, or the transfer case (if equipped) is
shifted from 4WD LO or Neutral, back to 4WD LOCK or
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AUTO, the ESP system will be in this mode. This mode
should be used for almost all driving situations. ESP
should only be turned to “Partial Off” or “ESP Off” for
specific reasons as noted below.ESP Partial Off
This mode is entered by momentarily depressing the ESP
OFF switch. When in
Partial Offmode, the TCS portion
of ESP, except for the “limited slip” feature described in
the TCS section, has been disabled and the ESP/TCS
Indicator Light will be illuminated. All other stability
features of ESP function normally. This mode is intended
to be used if the vehicle is in deep snow, sand, or gravel
conditions and more wheel spin than ESP would nor-
mally allow is required to gain traction. To turn ESP on
again, momentarily depress the ESP OFF switch. This
will restore the normal “ESP On” mode of operation.
NOTE: To improve the vehicle’s traction when driving
with snow chains, or starting off in deep snow, sand or
gravel, it may be desirable to switch to the “Partial Off”
mode by pressing the ESP OFF switch. Once the situation
requiring ESP to be switched to the “Partial Off” mode is
ESP OFF Switch
342 STARTING AND OPERATING

•
Each time the ignition is turned ON, the ESP System
will be ON even if it was turned off previously.
•
The ESP Control System will make buzzing or clicking
sounds when it is active. This is normal. The sounds
will stop when ESP becomes inactive following the
maneuver that caused the ESP activation.
TSC (Trailer Sway Control)The TSC system uses sensors in the vehicle to recognize
an excessively swaying trailer and will take the appro-
priate actions to attempt to stop the sway. The system
may reduce engine power and apply the brake of the
appropriate wheel(s) to counteract the sway of the trailer.
TSC will become active automatically once an excessively
swaying trailer is recognized. No driver action is re-
quired. Note that TSC cannot stop all trailers from
swaying. Always use caution when towing a trailer and
follow the trailer tongue weight recommendations. Refer
to “Trailer Towing” in Section 5 of this manual for moreinformation on towing a trailer with your vehicle. When
TSC is functioning, the “ESP/TCS Indicator Light” will
flash, the engine power may be reduced and you may
feel the brakes being applied to individual wheels to
attempt to stop the trailer from swaying. TSC is disabled
when the ESP system is in the Partial Off or Full Off
modes.
TSC is only active in the default “ESP On” mode. TSC can
be disabled by pressing the ESP OFF switch and entering
“ESP Partial Off” mode. It is not active in the “ESP Partial
Off” or “ESP Off” modes. Please refer to the ESP portion
of this section for an explanation of the different ESP
operating modes.
WARNING!
If TSC activates while driving, slow the vehicle
down, stop at the nearest safe location, and adjust the
trailer load to eliminate trailer sway.
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loading may be required for high-speed vehicle opera-
tion. Refer to original equipment or an authorized tire
dealer for recommended safe operating speeds, loading
and cold tire inflation pressures.
WARNING!
High speed driving with your vehicle under maxi-
mum load is dangerous. The added strain on your
tires could cause them to fail. You could have a
serious accident. Do not drive a vehicle loaded to the
maximum capacity at continuous speeds above
75 mph (120 km/h).
Radial Ply Tires
WARNING!
Combining radial ply tires with other types of tires
on your vehicle will cause your vehicle to handle
poorly. The instability could cause an accident. Al-
ways use radial ply tires in sets of four (or six, in case
of trucks with dual rear wheels). Never combine
them with other types of tires.
Cuts and punctures in radial tires are repairable only in
the tread area because of sidewall flexing. Consult your
authorized tire dealer for radial tire repairs.Tire SpinningWhen stuck in mud, sand, snow, or ice conditions, DO
NOT spin your vehicle’s wheels faster than 30 mph
(48 km/h) or for longer than 30 seconds continuously
without stopping when you are stuck.
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