2020 CHEVROLET LOW CAB FORWARD check engine

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Instruments and Controls 77
Exhaust System Warning Light
EXH. SYSTEM
This light comes on when the SCR
system detects a malfunction or
incorrect DEF. SCR system will turn
on other indicator lights and reduce
engine power in progressive stages
to encourage you to have the
malfunction corrected. Continuing to
drive for too long after this light
turns on will eventually result in a
severe vehicle speed limitation.
If this light turns on, promptly have
the vehicle inspected and serviced
at your dealer. SeeDiesel Exhaust
Fluid 0180.
Refill Diesel Exhaust Fluid
(DEF) Warning Light
REFILL DEF
This message displays and a
warning light appears when the DEF
tank is almost empty. Add DEF as
soon as possible.
Engine power will be reduced and
vehicle speed will be limited when
this light is activated. Failure to
promptly refill the DEF tank will result in a severe vehicle speed
limitation. See
Diesel Exhaust Fluid
0 180.
When DIC ERROR is Displayed
ERROR
If the system has not yet been able
to access maintenance data,
ERROR is shown on the DIC.
If ERROR does not change
automatically to a distance or other
maintenance indication, have your
vehicle serviced at your dealer.
Maintenance Data Indicator
Lights
Maintenance data indicator lights
appear on the DIC when each
maintenance item is selected or
when the next change or service
interval of the item is near or has
been reached.
The distance or time shown is the
remaining or excess of them to /
from the change or service timing.
The positive distance or time shows
the remaining of that and the
negative distance or time shows the excess of that. For the items listed
below, the displayed color will
change from green to amber when
remaining distance is below
1 600 km (1,000 mi) and the screen
is selected.
These screens are also displayed
when the engine control switch
turns to the ON position after above
notification timing. The message
remains on the display until the DIC
selector is pressed once or the
vehicle is started.
The maintenance data function
indicates the distance remaining
before the next scheduled
maintenance. Scheduled
maintenance time is approaching
when the display turns from green
to amber. Have the vehicle checked
and serviced at your dealer as soon
as possible.
The vehicle needs to be maintained
more often if it is driven in severe
conditions.

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Lighting 83
lever is held up or down. The lever
moves back to neutral as soon as it
is released.
A green light on the instrument
panel is designed to flash to tell you
that the front and rear turn signal
lights are working. If the light stays
on, but does not flash, check for a
burned-out turn signal bulb. If the
green light does not come on when
you move the lever, check the fuse
and indicator bulb.
Either of these indicator lights
flashes when the turn signal switch
is operated with the engine control
switch in the ON position.
Cornering Lamps
The cornering light illuminates the
area to which the vehicle is turning.
With the headlights or marker lights
on, the cornering lights come on in
coordination with the turn signal
lights.
SeeExterior Lamp Controls 080
and
Bulb Replacement 0267.
Interior Lighting
Instrument Panel
Illumination Control
The control will change the light
level of the instrument panel.

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Infotainment System 93
If Error Appears in the Display
The following messages are
displayed (blink) according to the
status.
.LOAD: This message is
displayed right after inserting a
disc into the main unit or while
reading TOC
. READING: This message is
displayed when reading the file
format of the disc in the MP3/
WMA mode.
. CD CHECK: This message is
displayed when the disc is
stained or upside-down. This
message is displayed when a
disc reading error or a
media-dependent error occurs,
including when a blank disc is
inserted. Check the disc in the
player.
. DECK ERROR: This message is
displayed when the player
cannot operate for some reason.
Eject the disc from the audio
system. .
NO SUPPORT: This message is
displayed when the disc is in
one of the following conditions:
‐Not in
ISO9660 Level 1, 2 format
‐ Not containing MP3/WMA data
(including MP3/WMA
extension files)
‐ Containing only SKIP FILEs
If a disc cannot be ejected, please
contact nearest dealer for service.
Using the Compact Disc
System
Disc
When it is cold or when it is raining,
the car windows will fog up and
cause condensation (water drops) to
form in the vehicle compartment.
When this happens, the audio may
skip, and playback will stop.
Ventilate the vehicle compartment
and dehumidify before
resuming use.
The audio may skip due to violent
vibrations when the car is traveling
across harsh roads. Never insert foreign objects into the
disc insertion slot.
Do not insert a wet disc into the
player.
This player uses an invisible laser
beam which could cause hazardous
radiation exposure if directed
outside the player. Be sure to
operate the player correctly.
Playback may not be possible due
to recording conditions or disc
characteristics, scratches, dirt,
or deterioration.
Usable Discs
Music CDs with the following marks
can be used. CD-R and CD-RW
discs recorded according to the
CD-DA format can also be played.
.
CD-R (CD-Recordable), CD-RW
(CD-ReWritable) may not be
able to play back due to the
recording condition,
characteristics of the disc,
damage, dirt or deterioration due
to long exposure to the
environment of the vehicle
compartment. CD-R, CD-RW

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Infotainment System 97
File Names
Only files with the MP3/WMA file
extension mp3, .wma can be
recognized as MP3/WMA and
played. Be sure to save MP3 files
with the mp3 file extension. Be sure
to use the .wma file extension when
saving WMA files. The MP letters of
the file extension will be recognized
whether entered as uppercase
letters or lowercase letters.
If the .mp3 or .wma file extension is
attached to a file other than an MP3/
WMA file, that file will be mistakenly
recognized by the deck as an MP3/
WMA file and played, resulting in
loud noise output that can damage
the speakers. Be sure to avoid
attaching the mp3 or .wma file
extension to files that are not MP3/
WMA files.
Multi-Sessions
Does not support multi-session.
When the disc used is a
multi-session disc, only the first
session will be played.Playing MP3/WMA
When a disc with recorded MP3/
WMA files is inserted, the player
first checks all the files on the disc.
No sound is emitted while the player
is checking the files on the disc. It is
recommended that the disc should
be recorded without files other than
MP3/WMA files and without
unnecessary folders in order to
speed up the checking of disc files
by the player.
MP3/WMA Playing Time Display
It is possible that playing time will
not be correct, depending on the
writing condition of the MP3/WMA
file or when VBR Fast Up/Down is
operated.
Display Order of MP3/WMA File/
Folder Names
Names of MP3/WMA folders and
files within the same level are
displayed in the following order.
1. MP3/WMA folders displayed first, by ascending order of
numbers, letters. The files stored just below the root of the
disc will be stored in the ROOT
FOLDER.
2. Files displayed next, by ascending order of numbers,
letters. It is assumed here that
a disc has already been loaded
into the unit.
This unit reconfigures the folders
created by a user as shown below.

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
98 Infotainment System
The following operations are based
on the sample MP3/WMA file
structure given above.
When a disc is inserted, the CD
player screen will be displayed for
about a few seconds while the unit
checks whether the CD is an audio
CD or whether it contains MP3/
WMA data.Normally, tracks in ROOT FOLDER
will be played in order from the
first file.
USB Port
USB Operation
Playing Music Files in the USB
Memory (When the USB Memory
is not Connected)
When the USB Memory is
connected to the USB terminal
users can listen to music in the USB
Memory.
1. Connect the USB Memory to the USB terminal.
2. Press MODE/
O/ENTER.
3. Turn MODE/
O/ENTER to
select USB, and then press
ENTER.
The music file starts playing.
Playing Music Files in the USB
Memory (When the USB Memory
is Connected)
1. Press MODE/
O/ENTER.
2. Turn MODE/
O/ENTER to
select USB, and then press
ENTER.

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Infotainment System 101
If an Error Appears in the Display
The following messages are
displayed (blink) according to the
status.
READING: This message is
displayed when reading the file
format of the USB devices.
USB ERROR 1: This message is
displayed when the player cannot
operate for some reason.
Disconnect the USB device from the
audio system.
USB ERROR 2: This message is
displayed when the connected USB
device is disabled. Connect another
USB device.
USB ERROR 3: This message is
displayed when the USB hub is
connected. Remove the USB hub
from the audio system.
NO MUSIC: This message is
displayed when a blank USB device
or the USB device that does not
contain files with playback
extensions is connected.READ ERROR: This message is
displayed if a problem is detected in
the USB device. Disconnect the
USB device, and check the USB
device itself.
NO SUPPORT: This message is
displayed when the USB device
contains no MP3/WMA data
(including MP3/WMA extension
files) or contains only SKIP FILEs.
iPod Operation
When an iPod is connected to the
USB terminal using an iPod
connection cable, users can operate
the iPod from the main unit and
listen to music on the iPod.
See the instruction manual for the
iPod Connection Cable on how to
connect and set the connection
cable.
Playing Music Files in the iPod
(When the iPod is not Connected)
1. Use an iPod connection cable, and connect the iPod to the
USB terminal.
2. Press MODE/
O/ENTER. 3. Turn MODE/
O/ENTER to
select IPOD, and then press
ENTER.
READING is displayed, and it
takes a few seconds to
recognize the music files in the
iPod. When the music files in
the iPod are recognized, iPod
playback begins. It will start the
playback with the music file
that was playing on the iPod
before it was connected to the
main unit. If the main unit
cannot detect that file, it will
start playing from the first
music file.
Playing Music Files in the iPod
(When the iPod is Connected)
1. Press MODE/
O/ENTER.
2. Turn MODE/
O/ENTER to
select IPOD, and then press
ENTER. The music file starts
playing.

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Infotainment System 105
MessageDescription
READING This message is displayed when
reading the file format of the iPod.
READ ERROR This message is displayed if a
problem is detected in the iPod.
Disconnect the iPod, and check the
iPod itself.
COMM ERROR This message is displayed when an
iPod communication error occurs.
Reconnect the iPod connection
cable.
NO SONGS This message is displayed when a
blank iPod is connected.
NO PLAYLIST This message is displayed when a
blank PLAYLIST is selected.
USB Devices
USB Memory Standards
.
Compatible file system :
FAT16/32
. Audio format that is playable :
MP3/WMA
. Compatibility : USB2.0 (Full
speed) .
Compatible Device: USB mass
storage class
This system is not compatible with
external hard drive units (pocket
hard disk drives). Connections using
HUB, etc. are not supported.
Playable MP3 File Standards
. Supported standards: ‐
MPEG-1 Audio Layer III
‐ MPEG-2 Audio Layer III
. Supported sampling frequencies:
‐MPEG-1: 32, 44.1, 48 (kHz)
‐ MPEG-2: 16, 22.05, 24 (kHz)
. Supported bit rate:
‐MPEG1: 32, 40, 48, 56, 64,
80, 96, 112, 128, 160, 192,
224, 256, 320 (kbps)
‐ MPEG2: 8, 16, 24, 32, 40, 48,
56, 64, 80, 96, 112, 128,
160 (kbps)
. Variable bit rate (VBR) is
supported.
. Does not support free format.
. Digital Rights Management
(DRM) is not supported.
. Supported channel modes:
stereo, joint stereo, dual
channel, monaural
Playable WMA File Standards
. Supported standards:
. Supported sampling frequencies:
32, 44.1, 48 (kHz)

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
128 Driving and Operating
Driving and
Operating
Driving Information
Driver Behavior . . . . . . . . . . . . . . . 129
Driving for Better FuelEconomy . . . . . . . . . . . . . . . . . . . . 129
Distracted Driving . . . . . . . . . . . . 130
Control of a Vehicle . . . . . . . . . . . 130
Braking . . . . . . . . . . . . . . . . . . . . . . . 134
Steering . . . . . . . . . . . . . . . . . . . . . . 140
Driving on Wet Roads . . . . . . . . 140
Hill and Mountain Roads . . . . . 141
Winter Driving . . . . . . . . . . . . . . . . 142
If the Vehicle Is Stuck . . . . . . . . 144
Emergencies (Troubleshooting) . . . . . . . . . . . 145
Emergencies (Disabled Vehicle) . . . . . . . . . . . . . . . . . . . . . 155
Starting and Operating
New Vehicle Break-In . . . . . . . . . 156
Pedals . . . . . . . . . . . . . . . . . . . . . . . . 157
Ignition Positions . . . . . . . . . . . . . 157
Starting and Stopping theVehicle . . . . . . . . . . . . . . . . . . . . . . 159
Operating Temperature . . . . . . . 162
Winter Cover . . . . . . . . . . . . . . . . . 163 Engine Heater . . . . . . . . . . . . . . . . 163
Engine Alarm and Automatic
Shutdown . . . . . . . . . . . . . . . . . . . 164
Idle Shutdown . . . . . . . . . . . . . . . . 164
High Idle System . . . . . . . . . . . . . 165
Engine Checks Before Operating . . . . . . . . . . . . . . . . . . . 166
Parking over Things That Burn . . . . . . . . . . . . . . . . . . . 167
Engine Exhaust
Engine Exhaust . . . . . . . . . . . . . . 168
Running the Vehicle WhileParked . . . . . . . . . . . . . . . . . . . . . . 170
Diesel Particulate Filter
Diesel Particulate Filter . . . . . . . 171
Diesel Exhaust Fluid
Diesel Exhaust Fluid . . . . . . . . . . 180
Automatic Transmission
Automatic Transmission . . . . . . 196
Selector Lever . . . . . . . . . . . . . . . . 205
Overdrive Off . . . . . . . . . . . . . . . . . 206
Brakes
Antilock BrakeSystem (ABS) . . . . . . . . . . . . . . . 207
Parking Brake . . . . . . . . . . . . . . . . 211
Exhaust Brake . . . . . . . . . . . . . . . . 213
Cruise Control
Cruise Control . . . . . . . . . . . . . . . . 214
Fuel
Fuel for Diesel Engines . . . . . . . 218
Biodiesel . . . . . . . . . . . . . . . . . . . . . 219
Cold Weather Operation . . . . . . 221
Water in Fuel . . . . . . . . . . . . . . . . . 221
Running Out of Fuel . . . . . . . . . . 224
Filling the Tank . . . . . . . . . . . . . . . 225
Conversions and Add-Ons
Add-On Electrical Equipment . . . . . . . . . . . . . . . . . . 227
Power Take-Off (PTO) . . . . . . . . 227