check engine CHEVROLET LOW CAB FORWARD 2018 Workshop Manual

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
170 Driving and Operating
the selectable (switch) regeneration
required warning light (red) is
displayed on the DIC.
Continued driving without
performing DPF regeneration will
cause the check engine malfunction
indicator light and reduced engine
power indicator light to come on, an
engine power reduction, and may
cause damage to the DPF filter. See
Vehicle Messages086.
The time needed to complete
regeneration differs depending on
the outside temperature.
The exhaust brake is activated
during DPF regeneration. The
exhaust brake starting to operate or
being disengaged will produce a
sound, but this does not indicate a
failure.
During regeneration, white smoke
may be temporarily produced from
the exhaust pipe. This results from
combustion of PM, it does not
indicate a failure.
Regeneration is finished earlier
immediately after driving than when
the engine is cold. The engine coolant temperature
may rise during regeneration.
DPF Regeneration during
Prolonged Idling
DPF regeneration may be initiated
automatically during prolonged
idling. If regeneration is initiated, the
regeneration in progress indicator
light (amber) comes on but this is
normal and does not indicate a
failure.
If driving is started or the PTO is
connected during DPF regeneration
by prolonged idling, the selectable
(switch) regeneration required
warning light (amber) comes on and
regeneration is suspended. Perform
Switch regeneration procedure in
order to complete the DPF
regeneration.
Prolonged idling may require more
frequent DPF regeneration.
See
Driver Information Center (DIC)
0 82.Diesel Exhaust Fluid
Diesel exhaust fluid (DEF) is used
exclusively for the selective catalytic
reduction (SCR) system. Be sure to
use only API certified DEF. When
the SCR system detects DEF level
is nearly empty or incorrect fluids
(such as water or low concentrated
DEF.) are added, the SCR system
will turn on warning and indicator
lights and reduce engine power in
progressive stages to encourage
you to have the condition corrected.
Continuing to drive for too long after
these lights come on will eventually
result in a severe vehicle speed
limitation. See Vehicle Messages
0 86
The DEF freezes below −11 °C
(12 °F). The SCR system is
equipped with a heating function
which utilizes the engine coolant, so
the engine can be started even
when DEF is frozen.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
182 Driving and Operating
Stage 1 :When incorrect DEF or an
SCR system malfunction (Type A) is
detected, the warning and indicator
lights will come on as shown in the
table and engine power will be
reduced so the vehicle speed will
not exceed 89 km/h (55 MPH).
Stage 2 : If driving is continued for
another approximately
160 km (100 miles), the warning and
indicator lights will begin blinking.
Again, engine power will be reduced
so the vehicle speed will not exceed
56 km/h (35 MPH).
Stage 3 : If driving is continued for
approximately
105 more km (65 miles), the warning
and indicator lights will begin to
blink faster. Engine power will still
be reduced so the vehicle speed will
not exceed 56 km/h (35 MPH). The
vehicle speed will be limited to
8 km/h (5 MPH) either when the
vehicle is stopped after driving
further on (approximately
8 km (5 miles)) or when the engine
is restarted. Stage 4 :
DEF indicator light is
blinking quickly, the other warning
lights are on and the buzzer is
beeping continuously indicates the
vehicle speed is limited to 8 km/h (5
MPH). See Vehicle Messages 086,
Malfunction Indicator Lamp (Check
Engine Light) 074, Diesel Exhaust
Fluid (DEF) Warning Light 080, and
Reduced Engine Power Light 081.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Driving and Operating 185
When the exhaust system warning
light comes on, promptly have the
vehicle inspected and serviced at a
dealer.
When a malfunction is detected in
the SCR system, the warning and
the indicator lights shown in the
table come on. SeeVehicle
Messages 086, Malfunction
Indicator Lamp (Check Engine
Light) 074, and Diesel Exhaust
Fluid (DEF) Warning Light 080.
When the Diesel Exhaust Fluid
(DEF) Tank is Empty
If the DEF tank is empty and
warning and indicator lights are on,
you must follow below procedure to
cancel the vehicle restriction: 1. Turn the engine control switch to the LOCK or ACC position,
and add DEF.
2. After adding DEF, turn the engine control switch to ON
position.
3. Wait until buzzer stops, warnings and indicators are
turned off. 4. If the buzzer does not stop,
return the engine control switch
back to the LOCK position and
add more DEF, and then start
over from step 2 above.
5. Restart the engine.
It may take a while until the warning
lights and indicators turn off and the
buzzer stops after turning the
engine control switch to the ON
position.
It is desirable to fill up the tank with
DEF to avoid DEF remaining level
warning indication from reappearing.
When the outside temperature is
low, refer to Adding DEF in Cold
Weather. See Driver Information
Center (DIC) 082, Brake System
Warning Light (Parking Brake Light)
0 75, Warning Buzzers 091, and
Winter Driving 0133.Automatic
Transmission
On an automatic transmission
vehicle, the driver does not use a
clutch pedal when pulling away,
changing gears, or stopping. Only
the selector lever, accelerator pedal,
and brake pedal are used.
Practice learning the characteristics
of the automatic transmission
vehicle and how to correctly operate
it. When the vehicle is stationary,
remember to keep the brake pedal
firmly pressed, and if necessary,
move the selector lever in the P or
N position and apply the parking
brake.
Creep : With the engine running
and a gear position other than P or
N selected with the selector lever,
power reaches the wheels even
when the accelerator pedal is not
pressed, causing the vehicle to tend
to move.
Furthermore, the higher the engine
speed, the stronger the creep and
the greater the vehicle's tendency
to move.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
186 Driving and Operating
Starting
Start the engine in either the P or
the N position. The engine should
not start in any other selector
position. If it does, something is
wrong. Have your truck checked by
your dealer as soon as possible.
Always apply either the foot brake
or the parking brake before shifting
into any driving position. This will
prevent creeping.
The engine should be running at
idle when shifting from P or N to one
of the driving positions. See
Selector Lever0194.
Caution
Do not apply water from a
high-pressure washer nozzle
directly to the electric connectors.
Failure to observe this precaution
can lead to faulty operation of the
electrical system.
Caution
Never move the selector into the
P position when the vehicle is in
motion. This will damage the
automatic transmission.
Firmly press the brake pedal to
prevent the vehicle from moving
even if it is stopped on a level road,
and move the selector lever into P
and firmly apply the parking brake
as needed.
The engine speed rises and
creeping will be stronger than usual
during the conditions noted below.
Keep the brake pedal firmly
pressed:
. Immediately after engine
start up.
. While the air conditioner is
running.
. During the diesel particulate filter
(DPF) regeneration. How to Use the Automatic
Transmission{Warning
Before starting the engine, move
the selector lever into P or N (P is
preferred), make sure the shift
indicator indicates P or N, pull up
the parking brake lever and firmly
press the brake pedal.
When moving the selector lever to
any position other than P, be sure
to press the brake pedal.
Never leave the driver's seat with
the selector lever placed in D, 2,
1 or R. The vehicle may start
moving. When leaving the driver's
seat, be sure to move the selector
lever into P and securely set the
parking brake.
When you move the selector lever
into D, 2, 1 or R, creep will cause
the vehicle to move.
(Continued)

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Driving and Operating 187
Warning (Continued)
When pulling away from a
standstill, you must control the
speed using only the accelerator
pedal. Operate the accelerator
pedal carefully.
Do not operate the selector lever
while pressing the accelerator
pedal. The vehicle may make a
sudden start, possibly causing an
accident.
You and others could be seriously
injured.
When pulling away, visually check
the position of the selector lever.
If you always press the push button
while operating the selector lever,
the lever may occasionally move to
the other gear position against your
intentions.
Practice operating the selector lever
between the N and D without
pressing the push button. Do not operate the selector lever
while pressing the accelerator
pedal. Doing so is dangerous
because the vehicle would
suddenly move.
Do not operate the automatic
transmission at or near stall
condition for more than
five seconds. Stall condition is when
the transmission is in one of the
driving ranges, the engine is running
at high speed, but the drive wheels
are unable to move. This condition
might occur if the vehicle is stuck in
deep sand or is pushing against a
fixed barrier. Operating the
transmission at stall condition will
result in overheating and damage.
Do not hold your vehicle on an
upgrade with the accelerator pedal.
Doing so will result in automatic
transmission overheating and
damage. Use the parking brake or
foot brake to hold the vehicle on an
upgrade.
Even if you plan to move only a
short distance, sit in the correct
driving position and make sure you
can firmly press the brake and
accelerator pedals.
When you reverse, you twist to look
rearward so pedal operation
becomes difficult. Firmly press the
brake pedal. Also, practice returning
the selector lever immediately to the
N position after reversing. When
pulling away, visually check the
selector lever position and the shift
indicator.
When the vehicle is stopped, do not
keep pressing the accelerator pedal
with the selector lever in a forward
gear or R position while pressing
the brake pedal. Doing so may
cause a breakdown.
Sit in the correct driving position,
and use your right foot to operate
the brake and accelerator pedals.
To avoid accidentally pressing the
wrong pedal, check the pedal
positions and practice putting your
foot on the desired pedal.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
188 Driving and Operating
To start your vehicle:1. Firmly press the brake pedal. After making sure the selector
lever is placed into P or N, that
P or N is shown in the shift
indicator and that the parking
brake lever is fully pulled up,
place the engine control switch
into the ON position.
2. Start the engine and move the selector lever into D for forward
movement, or R for backward
movement while firmly pressing
the brake pedal with your
right foot.
3. Make sure that the shift indicator indicates the correct
gear (D for forward movement,
or R for backward movement),
release the parking brake,
release the brake pedal, and
then gradually press the
accelerator pedal. The vehicle
starts moving as you press the
accelerator pedal further. On a steep slope:
Make sure that the shift indicator
indicates the correct gear (D for
forward movement, or R for
backward movement), check the
area around the vehicle is clear,
release the brake pedal with your
right foot, and then slowly press the
accelerator pedal.
After you feel the vehicle start
moving, gradually release the
parking brake lever and start driving
the vehicle.
When the brake pedal is not
pressed, the shift lock system
operates and the selector lever
cannot be shifted from P to any
other position.
See
Driver Information Center (DIC)
0 82, Starting and Stopping the
Vehicle 0149, Selector Lever 0194,
and Automatic Transmission Shift
Lock Control Function Check 0251.
Normal Driving
When you move the selector lever
from P into D, shifting takes place in
the automatic mode. Check that D is
displayed in the shift indicator. If the automatic transmission fluid
temperature is too low, the
transmission may not initially make
automatic shift to the 4th, 5th, and
6th gear. This condition is normal
and will be resolved as the fluid
temperature rises.
To Accelerate
To accelerate when the accelerator
pedal is pressed further, kickdown
operates and the speed increases.
The transmission will downshift at
speeds below 88 km/h (55 MPH), to
provide greater acceleration.
Kickdown
If you press the accelerator pedal
fully while driving, in accordance
with the current speed the gear
automatically shifts down and the
engine speed rises, enabling
sufficient acceleration. This is called
kickdown.
You can easily accelerate to the
required speed when overtaking
other vehicles or when joining traffic
on a highway. In order to maintain
speed when driving on an uphill
road, as you gradually press the

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
190 Driving and Operating
SeeAutomatic Transmission Fluid
Temperature Warning Light 078.
To Stop Your Vehicle 1. To temporarily stop the vehicle, press the brake pedal firmly
while the selector lever is in D.
2. Use the parking brake as required. Press the brake pedal
firmly, and firmly apply the
parking brake.
If the vehicle is stationary for a
long time, move the selector
lever into the N or P position.
If the selector lever is kept in
D, the temperature of the
automatic transmission fluid
increases due to heat from the
torque converter.
To ensure reliable brake application,
be sure to use your right foot to
press the brake pedal.
When leaving the driver's seat,
follow the When Parking Your
Vehicle procedure. To Start After Stopping
To start again after stopping your
vehicle, visually check that the
selector lever is in D, and gradually
press the accelerator pedal to
pull away.
When Parking Your Vehicle
{Warning
Do not leave your vehicle while
the engine is still running. Do not
park with the selector lever in a
position other than P or N the
vehicle may begin moving by
itself due to creeping. You may
accidentally press the accelerator
pedal when getting into the
vehicle causing it to start moving
suddenly.
When parking the vehicle, always
apply the parking brake and move
the selector lever to the P
position.
(Continued)
Warning (Continued)
When parking on a slope, move
the selector lever in the P position
and block the wheels with chocks.
You and others could be seriously
injured.
1. Keep pressing the brake pedal firmly with your right foot, then
apply the parking brake.
2. Move the selector lever in the P position, check that the shift
indicator is indicating P, and
slowly ease your right foot off
the brake pedal.
3. Stop the engine and remove the key. When the selector
lever is not placed in the P
position, the shift lock system
operates and the key cannot
be removed.
See Starting and Stopping the
Vehicle 0149, and Parking Brake
0 200.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Driving and Operating 191
If you cannot move the selector
lever from the P position after
starting the engine, perform the
following necessary checks:
.Check that you are firmly
pressing the brake pedal.
. Check if the area where your
vehicle is parked is not a slope.
. If your vehicle is parked on a
downhill slope, the push
operation of the selector lever
may become heavy to move. In
this case, you can operate the
selector lever more smoothly by
pushing the selector lever
towards the front of the vehicle
while pushing the button.
Shift Lock System
When Starting Your Vehicle
The selector lever cannot be
operated from the P position to any
other position without the brake
pedal being pressed. Be sure to
operate the lever while pressing the
brake pedal. When Parking Your Vehicle
The key cannot be removed unless
the selector lever is securely placed
in the P position (key interlock
system). Be sure to place the
selector lever in the P position when
parking the vehicle.
The shift lock system is a system for
safety to prevent incorrect operation
of the automatic transmission. Use it
correctly and drive safely.
If You Cannot Move the Selector
Lever from the P Position
Caution
When the selector cannot be
operated from the P position to
any other position even after
performing the operation below
repeatedly, the shift lock system
may have a failure. Have the
vehicle inspected at your dealer.
If you cannot move the selector
lever from the P position after
starting the engine, perform the
following checks:
.
Check that you are firmly
pressing the brake pedal. When
the brake pedal is not pressed,
the shift lock system operates
and the selector lever cannot be
shifted from P to any other
position.
. Check if the area where your
vehicle is parked is not a slope.
. If your vehicle is parked on a
downside slope, the operation of
the selector lever may become
heavy to move. In this case, you
can operate the selector lever
more smoothly by moving the
selector lever towards the front
of the vehicle while pressing the
button.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
194 Driving and Operating
Selector Lever
Move the selector lever (2) to make
a shift into each gear position.
P (Parking) :Used when the
vehicle is parked or when starting
the engine. The P position is to be
used with the parking brake. The P
and N positions are the two
positions in which the engine can be
started.
R (Reverse) : Used when backing
up the vehicle. Bring the truck to a
complete stop before moving the
selector to the R position. N (Neutral) :
Can be used when
starting the engine, but for safety,
get in the habit of starting the
engine in the P position. The N
position is used should it become
necessary to tow your truck.
D (Drive) : The D position is for all
normal forward driving. The system
automatically selects the gear
according to the vehicle speed.
Press the overdrive off switch (3) to
switch to the overdrive ON position
for greater fuel economy.
2 (Second) : May be used when
driving on downhill roads or when
the engine brake is required. Select
the 2 position at speeds below
40 km/h (25 MPH) when traveling
down a moderate grade. Return the
selector to the D position for normal
driving.
1 (Low) : Used on steep downhill
roads or when strong engine
braking is required. Return the
selector to the D position for normal
driving.
{Warning
When pulling away, always
visually check the position of the
selector lever for safety.
Only push the button for gear
selection when necessary.
Pushing the button unnecessarily
may result in unintended gear
selection.
Never move the selector to the P
position when the truck is in
motion.
Do not run the vehicle with the
transmission in neutral. Not only
will the engine brake not function,
but the transmission will also be
damaged. You and others could
be seriously injured.
When repeatedly shifting between
forward and reverse gears for a
multiple-point turn, firmly press the
brake pedal and confirm that the
vehicle is completely stopped before
operating the selector lever.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Driving and Operating 195
For safety reasons, the shift lock
system operates to prevent shifting
of the selector lever to any position
other than P unless the brake pedal
is pressed and the starter switch is
in the ON position. When pulling
away, be sure to keep the brake
pedal pressed as you operate the
selector lever. SeeDriver
Information Center (DIC) 082,
Overdrive Off Light 079, Automatic
Transmission 0185, and Automatic
Transmission Shift Lock Control
Function Check 0251.
Overdrive Off
Overdrive Off Switch
Diesel vehicles have two overdrive
gears (5th and 6th). These two high
speed gears provide increased road
speed, low running noise and
outstanding fuel efficiency.
Take advantage of overdrive
whenever possible.
.
Use the overdrive during normal
driving. When driving down long
downhill roads that require the
engine brake, or when driving on mountain roads or through city
centers, release the overdrive.
Doing so will reduce the number
of gear changes making the ride
smoother.
. If your vehicle is traveling at a
speed exceeding
101 km/h (63 MPH), it is not
possible to downshift from 6th
gear to 5th gear.
. If your vehicle is traveling at a
speed exceeding
78 km/h (49 MPH), it is not
possible to downshift from 5th
gear to 4th gear.
Overdrive Off Switch : Under
normal circumstances, press the
overdrive off switch (3) to turn the
overdrive OFF (the overdrive off
indicator light comes on).
Press the switch again to release
the overdrive off (the overdrive off
indicator light goes off). See
Overdrive Off Light 079.