instrument cluster RAM CHASSIS CAB 2021 Service Manual

STARTING AND OPERATING135
Do Not Operate The Engine With Low Oil Pressure
When the engine is at normal operating temperature, the minimum oil pressures required are:
Do Not Operate The Engine With Failed
Parts

All engine failures give some warning before the
parts fail. Be on the alert for changes in
performance, sounds, and visual evidence that the
engine requires service. Some important clues are:

Engine misfiring or vibrating severely.
Sudden loss of power.
Unusual engine noises.
Fuel, oil or coolant leaks.

Sudden change, outside the normal operating
range, in the engine operating temperature.

Excessive smoke.
Oil pressure drop.
DIESEL PARTICULATE FILTER (DPF)
M
ANUAL REGENERATION - IF EQUIPPED
On equipped Chassis Cabs, a manual
regeneration can be enable through the
instrument cluster. The manual regeneration
will allow the DPF to complete a regeneration,
lowering the soot level without having to drive
the vehicle. The vehicle must be in PARK to
access this feature, and the fuel level must be
over 12.5% full. A message displaying the time
left on the regeneration will appear on the
instrument cluster, and the instrument cluster
will display the soot level Ú page 90.
ENGINE BLOCK HEATER — IF EQUIPPED
The engine block heater warms the engine, and
permits quicker starts in cold weather. Connect
the cord to a standard 110-115 Volt AC
electrical outlet with a grounded, three-wire
extension cord.
Gas Engine Only
The engine block heater cord is routed through
the grille by the right front tow hook.
It includes a removable cap that is secured by a
tethered strap. It also has a c-clip that is used
for storage when not in use for the Winter
months. During Winter months, remove the
heater cord wiring assembly from itself on the
c-clip.
Idle 700 to 800 RPM
10 psi (69 kPa)
Full speed and load 30 psi (207 kPa)
CAUTION!
If oil pressure falls to less than normal
readings, shut the engine off immediately.
Failure to do so could result in immediate and
severe engine damage.4

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138STARTING AND OPERATING
When the parking brake is applied with the
ignition switch ON, the “Brake Warning Light” in
the instrument cluster will illuminate.
NOTE:
When the parking brake is applied and the
transmission is placed in gear, the “Brake
Warning Light” will flash. If vehicle speed is
detected, a chime will sound to alert the
driver. Fully release the parking brake before
attempting to move the vehicle.
This light only shows that the parking brake is
applied. It does not show the degree of brake
application.
When parking on a hill, it is important to turn the
front wheels toward the curb on a downhill
grade and away from the curb on an uphill
grade. Apply the parking brake before placing
the gear selector in PARK, otherwise the load on
the transmission locking mechanism may make
it difficult to move the gear selector out of PARK.
The parking brake should always be applied
whenever the driver is not in the vehicle.
DIESEL EXHAUST BRAKE
(ENGINE BRAKING)
The purpose of the exhaust brake (engine
braking) feature is to supply negative (braking)
torque from the engine. Typically, the engine
braking is used for, but not limited to, vehicle
towing applications where vehicle braking can
be achieved by the internal engine power,
thereby sparing the mechanical brakes of the
vehicle.
Benefits of the exhaust brake are:
Vehicle driving control.
Reduced brake fade.
Longer brake life.
Faster cab warm-up.
WARNING!
Never use the PARK position as a substi -
tute for the parking brake. Always apply the
parking brake fully when parked to guard
against vehicle movement and possible
injury or damage.

Never leave children alone in a vehicle,
or with access to an unlocked vehicle.
Leaving unattended children in a vehicle is
dangerous for a number of reasons. A child
or others could be seriously or fatally injured.
Do not leave the key fob in or near the
vehicle, or in a location accessible to chil -
dren, and do not leave a vehicle equipped
with Keyless Enter-N-Go in the ACC or
ON/RUN mode. A child could operate power
windows, other controls, or move the vehicle.

Be sure the parking brake is fully disen -
gaged before driving; failure to do so can
lead to brake failure and a collision.
Always fully apply the parking brake when
leaving your vehicle or it may roll and cause
damage or injury. Also, be certain to leave
the transmission in PARK. Failure to do so
may cause the vehicle to roll and cause
damage or injury.
CAUTION!
If the Brake System Warning Light remains on
with the parking brake released, a brake
system malfunction is indicated. Have the
brake system serviced by an authorized
dealer immediately.

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STARTING AND OPERATING139
The exhaust brake feature will only function
when the driver toggles it on by pushing the
exhaust brake button until the "Exhaust Brake
Indicator" is illuminated. Normal (Full Strength)
exhaust brake mode is indicated by a yellow
"Exhaust Brake Indicator".

Exhaust Brake Switch

Once the "Exhaust Brake Indicator” is
illuminated and the vehicle is moving faster
than 5 mph (8 km/h); the exhaust brake will
automatically operate when the driver removes
pressure from the accelerator pedal. Exhaust
braking is most effective when the engine RPM
is higher. The automatic transmission will
downshift more aggressively in TOW/HAUL
mode when the exhaust brake is enabled to
increase brake performance. NOTE:
For optimum braking power it is recommended
to use the exhaust brake while in TOW/HAUL
mode.
The exhaust brake feature can also be used to
reduce the engine warm-up time. To use the
exhaust brake as a warm-up device, the vehicle
must be stopped or moving less than 5 mph
(8 km/h), the "Exhaust Brake Indicator" must be
on, and the coolant temperature must be below
180°F (82°C) and ambient temperature below
60°F (16°C).Automatic “Smart” Exhaust Brake
Automatic “Smart” Exhaust Brake technology
delivers smoother, less aggressive exhaust
braking characteristics during downhill
descents. Although it can apply full exhaust
braking force if needed, Automatic “Smart”
Exhaust Brake may not apply obvious braking if
the vehicle speed is not increasing. Automatic
“Smart” Exhaust Brake is intended to maintain
vehicle speed, while Full Exhaust Brake is
intended to reduce vehicle speed.
Automatic “Smart” Exhaust Brake can be
enabled by pushing the exhaust brake button
(on the center stack) again anytime after the
normal Full Exhaust Brake has been turned on.
The “Exhaust Brake Indicator” in the instrument
cluster display will change from Yellow to Green
when Automatic “Smart” Exhaust Brake is
enabled. Pushing the exhaust brake button
again will toggle the exhaust brake mode to off.WARNING!

Do not use the exhaust brake feature when
driving in icy or slippery conditions as the
increased engine braking can cause the rear
wheels to slide and the vehicle to swing around
with the possible loss of vehicle control, which
may cause an accident possibly resulting in
personal injury or death.

CAUTION!

Use of aftermarket exhaust brakes is not
recommended and could lead to engine damage

4

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STARTING AND OPERATING141
IGNITION PARK INTERLOCK

This vehicle is equipped with an Ignition Park
Interlock which requires the transmission to be in
PARK before the ignition can be turned to the OFF
mode. This helps the driver avoid inadvertently
leaving the vehicle without placing the
transmission in PARK. This system also locks the
transmission in PARK whenever the ignition is in
the OFF mode.

NOTE:
The transmission is NOT locked in PARK when
the ignition is in the ACC mode (even though the
engine will be off). Ensure that the transmission
is in PARK, and the ignition is OFF (not in ACC
mode) before exiting the vehicle.
BRAKE/TRANSMISSION SHIFT
I
NTERLOCK (BTSI) SYSTEM
This vehicle is equipped with a BTSI system that
holds the transmission gear selector in PARK
unless the brakes are applied. For vehicles with
8-speed transmission, to shift the transmission
out of PARK, the engine must be running and
the brake pedal must be pressed. The brake
pedal must also be pressed to shift from
NEUTRAL into DRIVE or REVERSE when the
vehicle is stopped or moving at low speeds.
For vehicles with 6-speed transmission, to shift
the transmission out of PARK, the ignition must
be in the ON/RUN mode (engine running or not)
and the brake pedal must be pressed.
The BTSI will timeout if brake pedal is pressed
for three minutes or longer continuously while in
park. It can be reset by releasing the brake for
more then three seconds, then reapplying the
brake pedal or cycling the ignition.
EIGHT-SPEED AUTOMATIC
T
RANSMISSION — IF EQUIPPED
The transmission is controlled using a rotary
electronic gear selector located on the
instrument panel. The transmission gear range
(PRND) is displayed both above the gear selector and in the instrument cluster. To select
a gear range, simply rotate the gear selector.
You must press the brake pedal to shift the
transmission out of PARK (or NEUTRAL, when
the vehicle is stopped or moving at low speeds).
To shift past multiple gear ranges at once (such
as PARK to DRIVE), simply rotate the gear
selector to the appropriate detent. Select the
DRIVE range for normal driving.
NOTE:
In the event of a mismatch between the gear
selector position and the actual transmission
gear (for example, driver selects PARK while
driving), the position indicator will blink continu
-
ously until the selector is returned to the proper
position, or the requested shift can be
completed.

The electronically-controlled transmission
adapts its shift schedule based on driver inputs,
along with environmental and road conditions.
The transmission electronics are self-calibrating;
therefore, the first few shifts on a new vehicle
may be somewhat abrupt. This is a normal
condition, and precision shifts will develop within
a few hundred miles (kilometers).

CAUTION!

Shift into or out of PARK or REVERSE only after
the vehicle has come to a complete stop.

Do not shift between PARK, REVERSE,
NEUTRAL, or DRIVE when the engine is
above idle speed.
Before shifting into any gear, make sure
your foot is firmly pressing the brake pedal.
4

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142STARTING AND OPERATING
(Continued)
Only shift from DRIVE to PARK or REVERSE
when the accelerator pedal is released and the
vehicle is stopped. Be sure to keep your foot on
the brake pedal when shifting between these
gears.
The transmission gear selector has only PARK,
REVERSE, NEUTRAL, and DRIVE positions.
Manual downshifts can be made using the
Electronic Range Select (ERS) shift control.
Pressing the GEAR -/GEAR + switches (on the
steering wheel) while in the DRIVE position will
select the highest available transmission gear,
and will display that gear limit in the instrument
cluster as 1, 2, 3, etc Úpage 145. Some
models will display both the selected gear limit,
and the actual current gear, while in ERS mode.

Electronic Transmission Gear Selector
Gear Ranges
Do not press the accelerator pedal when
shifting from PARK or NEUTRAL into another
gear range.
NOTE:
After selecting any gear range, wait a moment
to allow the selected gear to engage before
accelerating. This is especially important when
the engine is cold.
PARK (P)
This range supplements the parking brake by
locking the transmission. The engine can be
started in this range. Never attempt to use
PARK while the vehicle is in motion. Apply the
parking brake when exiting the vehicle in this
range.
When parking on a hill, apply the parking brake
before shifting the transmission to PARK. As an
added precaution, turn the front wheels toward
the curb on a downhill grade and away from the
curb on an uphill grade. NOTE:
On four-wheel drive vehicles be sure that the
transfer case is in a drive position.
When exiting the vehicle, always:
Apply the parking brake.
Shift the transmission into PARK.
Turn the engine off.
Remove the key fob.
WARNING!
Never use the PARK position as a substi
-
tute for the parking brake. Always apply the
parking brake fully when exiting the vehicle
to guard against vehicle movement and
possible injury or damage.
Your vehicle could move and injure you and
others if it is not in PARK. Check by trying to
move the transmission gear selector out of
PARK with the brake pedal released. Make
sure the transmission is in PARK before
exiting the vehicle.

21_DPF_OM_EN_USC_t.book Page 142

STARTING AND OPERATING145
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 may operate only in certain gears,
or may not shift at all. Vehicle performance may
be severely degraded and the engine may stall.
In some situations, the transmission may not
re-engage if the engine is turned off and
restarted. The Malfunction Indicator Light (MIL)
may be illuminated. A message in the
instrument cluster will inform the driver of the
more serious conditions, and indicate what
actions may be necessary.
In the event of a momentary problem, the
transmission can be reset to regain all forward
gears by performing the following steps:
NOTE:
In cases where the instrument cluster message
indicates the transmission may not re-engage
after engine shutdown, perform this procedure
only in a desired location (preferably, at an
authorized dealer).
1. Stop the vehicle.

2. Shift the transmission into PARK, if
possible. If not, shift the transmission to
NEUTRAL.
3. Push and hold the ignition switch until the engine turns off.
4. Wait approximately 30 seconds.
5. Restart the engine.

6. Shift into the desired gear range. If the problem is no longer detected, the
transmission will return to normal operation.

NOTE:
Even if the transmission can be reset, we
recommend that you visit an authorized dealer
at your earliest possible convenience. An autho -
rized dealer has diagnostic equipment to
assess the condition of your transmission.
If the transmission cannot be reset, authorized
dealer service is required.
Electronic Range Select (ERS) Operation
The ERS shift control allows the driver to
limit the highest available gear when the
transmission is in DRIVE. For example, if you set
the transmission gear limit to FOURTH gear, the
transmission will not shift above FOURTH gear
(except to prevent engine overspeed), but will
shift through the lower gears normally.

You can switch between DRIVE and ERS mode at
any vehicle speed. When the transmission gear
selector is in DRIVE, the transmission will operate
automatically, shifting between all available
gears. Tapping the GEAR – switch (on the
steering wheel) will activate ERS mode, display
the current gear in the instrument cluster, and
set that gear as the top available gear. Once in
ERS mode, tapping the GEAR – or GEAR + switch
will change the top available gear.

4

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146STARTING AND OPERATING

ERS Control

To exit ERS mode, simply push and hold the
GEAR + switch until the gear limit display
disappears from the instrument cluster.
When to Use TOW/HAUL Mode

When driving in hilly areas, towing a trailer, carrying
a heavy load, etc., and frequent transmission
shifting occurs, push the TOW/HAUL switch to
activate TOW/HAUL mode. This will improve
performance and reduce the potential for
transmission overheating or failure due to
excessive shifting.

TOW/HAUL Switch

The “TOW/HAUL Indicator Light” will illuminate in
the instrument cluster to indicate that TOW/HAUL
mode has been activated. Pushing the switch a
second time restores normal operation. Normal
operation is always the default at engine start-up.
If TOW/HAUL mode is desired, the switch must be
pushed each time the engine is started.

SIX-SPEED AUTOMATIC
T
RANSMISSION — IF EQUIPPED
Chassis Cab models may use either the
AS66RC or AS69RC transmission (which are
equipped with a Power Take-Off (PTO) access
cover on the side of the transmission case).

The transmission gear position display
(located in the instrument cluster) indicates the
transmission gear range. The gear selector is
mounted on the right side of the steering column.
You must press the brake pedal to move the gear
selector out of PARK
Ú
page 141. Pull the gear
selector toward you when shifting into REVERSE
or PARK, or when shifting out of PARK.

1 — GEAR + Switch
2 — GEAR – Switch
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 a collision or personal
injury.
WARNING!

Do not use the TOW/HAUL feature when driving
in icy or slippery conditions. The increased
engine braking can cause the rear wheels to
slide, and the vehicle to swing around with the
possible loss of vehicle control, which may
cause an accident possibly resulting in
personal injury or death.

21_DPF_OM_EN_USC_t.book Page 146

STARTING AND OPERATING147
(Continued)
The electronically-controlled transmission
provides a precise shift schedule. The
transmission electronics are self-calibrating;
therefore, the first few shifts on a new vehicle
may be somewhat abrupt. This is a normal
condition, and precision shifts will develop
within a few hundred miles (kilometers).
Only shift from DRIVE to PARK or REVERSE
when the accelerator pedal is released and the
vehicle is stopped. Be sure to keep your foot on
the brake pedal when shifting between these
gears.
The transmission gear selector has only PARK,
REVERSE, NEUTRAL, and DRIVE shift positions.
Manual downshifts can be made using the
Electronic Range Select (ERS) shift control.
Pushing the ERS (-/+) switches (on the steering
wheel) while in the DRIVE position will select the
highest available transmission gear, and will
display that gear limit in the instrument cluster
as 1, 2, 3, etc Ú page 150. Some models will
display both the selected gear limit, and the
actual current gear, while in ERS mode.Gear Ranges
Do not press the accelerator pedal when
shifting from PARK or NEUTRAL into another
gear range.
NOTE:
After selecting any gear range, wait a moment
to allow the selected gear to engage before
accelerating. This is especially important when
the engine is cold.
PARK (P)
This range supplements the parking brake by
locking the transmission. The engine can be
started in this range. Never attempt to use
PARK while the vehicle is in motion. Apply the
parking brake when exiting the vehicle in this
range.
When parking on a hill, apply the parking brake
before shifting the transmission to PARK,
otherwise the load on the transmission locking
mechanism may make it difficult to move the
gear selector out of PARK. As an added
precaution, turn the front wheels toward the
curb on a downhill grade and away from the
curb on an uphill grade. NOTE:
On four-wheel drive vehicles be sure that the
transfer case is in a drive position.
When exiting the vehicle, always:
Apply the parking brake.
Shift the transmission into PARK.
Turn the engine off.
Remove the key fob.
WARNING!
Never use the PARK position as a substi
-
tute for the parking brake. Always apply the
parking brake fully when exiting the vehicle
to guard against vehicle movement and
possible injury or damage.

Your vehicle could move and injure you and
others if it is not in PARK. Check by trying to
move the gear selector out of PARK with the
brake pedal released. Make sure the trans -
mission is in PARK before exiting the vehicle.

4

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150STARTING AND OPERATING
On trucks with AS66RC or AS69RC
transmission, FIFTH and SIXTH gears may
be inhibited briefly on cold starts below
41°F (5°C), and during very cold temperatures
(-4°F [-20°C] or below), operation may briefly
be limited to third gear only. During this
condition, the ability of the vehicle to accelerate
under heavily loaded conditions may be
reduced. In all cases, 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. If an
AS66RC/AS69RC equipped truck enters Limp
Home Mode at highway speeds, it will initially
engage FIFTH gear, until the vehicle slows to
a speed where THIRD gear can be engaged.
PARK, REVERSE, and NEUTRAL will continue to
operate. The Malfunction Indicator Light (MIL)
may be illuminated. Limp Home Mode allows the vehicle to be driven to an authorized dealer
for service without damaging 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 to the OFF position.
4. Wait approximately 10 seconds.
5. Restart the engine.

6. Shift into the desired gear range. If the
problem is no longer detected, the
transmission will return to normal operation.

NOTE:
Even if the transmission can be reset, we
recommend that you visit an authorized dealer
at your earliest possible convenience. An autho -
rized dealer has diagnostic equipment to
assess the condition of your transmission.
If the transmission cannot be reset, authorized
dealer service is required.
Electronic Range Select (ERS) Operation
The ERS shift control allows the driver to
limit the highest available gear when the
transmission is in DRIVE. For example, if you set
the transmission gear limit to FOURTH gear, the
transmission will not shift above FOURTH gear,
but will shift through the lower gears normally.
You can switch between DRIVE and ERS mode
at any vehicle speed. When the gear selector is
in the DRIVE position, the transmission will
operate automatically, shifting between all
available gears. Tapping the ERS (-) switch will
activate ERS mode, display the current gear in
the instrument cluster, and set that gear as the
top available gear. Once in ERS mode, tapping
(-) or (+) will change the top available gear.

21_DPF_OM_EN_USC_t.book Page 150

STARTING AND OPERATING151

Electronic Range Select

To exit ERS mode, simply push and hold the ERS
(+) switch until the gear limit display disappears
from the instrument cluster. NOTE:
To select the proper gear position for maximum
deceleration (engine braking), simply push and
hold the ERS (-) switch. 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 (FIFTH and SIXTH
gears). The transmission will automatically shift into
Overdrive if the following conditions are present:

The gear selector is in the DRIVE position.
The transmission fluid has reached an
adequate temperature.
The engine coolant has reached an adequate
temperature.
Vehicle speed is sufficiently high.

The TOW/HAUL switch has not been activated.

The driver is not heavily pressing the accelerator.

Torque Converter Clutch

A feature designed to improve fuel economy has
been included in the automatic transmission on
your vehicle. A clutch within the torque converter
engages automatically at calibrated speeds.
This may result in a slightly different feeling or
response during normal operation in the upper
gears. When the vehicle speed drops or during
some accelerations, the clutch automatically
disengages.

NOTE:
The torque converter clutch will not engage,
until the transmission fluid and engine
coolant are warm (usually after 1 to 3 miles
(2 to 5 km) of driving). Because engine speed
is higher when the torque converter clutch is
not engaged, it may seem as if the transmis
-
sion is not shifting properly when cold; This is
normal. Using the Electronic Range Select
(ERS) shift control, when the transmission is
sufficiently warm, will demonstrate that the
transmission is able to shift into and out of
Overdrive.
1 — GEAR + Switch
2 — GEAR – Switch
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 a collision or personal injury.

CAUTION!
When using ERS for engine braking while
descending steep grades, be careful not to
overspeed the engine. Apply the brakes as
needed to prevent engine overspeed.4

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