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Chevrolet Low Cab Forward 5.2L Diesel Engine 4500/5500 Series (GMNA-
Localizing-U.S.-12407814) - 2019 - crc - 12/13/17
Instruments and Controls 87
Low Coolant Warning Light
LOW COOLANT
If this message and light come on,
the system is low on engine coolant
and the engine may overheat.
A warning tone also sounds. If this
light comes on while driving, stop
the vehicle immediately and check
the cooling system for leaks. See
Engine Coolant0253 and have the
vehicle serviced by your dealer. This
light will also activate the engine
alarm and automatic shutdown
system.
See Engine Alarm and Automatic
Shutdown 0173 andEngine
Shutdown Warning Light 080.
Water Separator (Fuel Filter)
Warning Light
WATER SEPARATOR
This message displays and a
warning light appears when the
level in the water separator on the
fuel line is beyond the specified
level. Drain water following the
instructions in the Water in Fuel section and make sure the warning
light goes out. See
Water in Fuel
0 231.
If you continue driving with the
message displayed, the fuel
injection system may fail. See Water
in Fuel 0231.
Air Cleaner Light
CHECK AIR FILTER
This message displays and a
warning light appears when the next
air cleaner element service interval
is near or has already been
reached.
Replace the air cleaner element.
See Engine Air Cleaner/Filter 0253.
Low Fuel Warning Light
LOW FUEL
This message displays and a
warning light appears when the fuel
level in the tank becomes too low
while the engine is running. Add fuel
at the earliest possible time. If the
vehicle runs out of fuel, air bleeding
procedure must be performed. See
Fuel for Diesel Engines 0227,
Fuel Gauge 071, and Running Out
of Fuel 0233.
Regeneration Required
Warning Light
REGEN. REQUIRED
This light (amber) comes on when
Running regeneration or Switch
regeneration is required. When this
light comes on, perform DPF
regeneration soon. If the engine
continues to run without performing
DPF regeneration, this light will
change color from amber to red.
If this light turns red, perform DPF
regeneration immediately. If you do
not perform DPF regeneration, the
check engine malfunction indicator
light and reduced engine power
indicator light will come on,
imposing performance restriction on
the vehicle. If this happens, the
vehicle must be serviced at your
dealer. See Diesel Particulate Filter
0 180.
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Chevrolet Low Cab Forward 5.2L Diesel Engine 4500/5500 Series (GMNA-
Localizing-U.S.-12407814) - 2019 - crc - 12/13/17
Driving and Operating 233
2. Loosen the drain plug andmove the priming pump (1) up
and down by hand between
10 and 20 times.
3. Fully tighten the drain plug (2) and move the priming pump (1)
several times.
Fuel Filter (Engine-side)
1. Attach a plastic hose to the drain plug (2) on the bottom of
the engine-side fuel filter (1)
and put the other end of the
hose in a container placed
beneath the filter.
2. Loosen the drain plug andmove the priming pump up and
down by hand between 10 and
20 times.
3. Fully tighten the drain plug and move the priming pump several
times.
4. Test run the engine and check that there are no fuel leaks
from the drain plug of the
engine-side fuel filter. Also
check that the water separator
(fuel filter) warning light
stays off.
Running Out of Fuel
When the Fuel Tank is Empty
When the fuel tank is empty, air will
enter the fuel system, so refueling
alone will not be enough to restart
the engine. Use the following
methods to bleed the fuel system.
Bleeding the Fuel System
Steps for Refueling
1. Follow the directions in "Parking Brake Lever" under
Parking Brake 0220.
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Chevrolet Low Cab Forward 5.2L Diesel Engine 4500/5500 Series (GMNA-
Localizing-U.S.-12407814) - 2019 - crc - 12/13/17
Driving and Operating 235
Insufficient air bleeding can result in
faulty engine operation. Be sure,
therefore, to always carry out the
previous steps under "After starting
the engine".
Filling the Tank
Be sure to obey the following
instructions when refueling the
vehicle:
.Stop the engine and close the
vehicle's doors and windows.
. Keep cigarettes and other
flames away from the vehicle.
. Before opening the fuel tank
filler cap, touch a metallic object
to discharge static electricity
from your body.
. When filling, place the nozzle
deeply into the fuel tank. If you
try to fill more fuel by pulling out
the nozzle from the fuel tank, the
fuel may spill out, thus causing
danger.
. Be sure to wipe off the fuel that
is spilled at refueling.
{Warning
Fuel vapor is highly flammable.
Be careful not to inhale fuel vapor
when refueling the vehicle.
If you have a static charge
buildup on your body while
refueling the vehicle, a spark
caused by its discharge could
ignite the fuel, resulting in burns.
All parts of the refueling
procedure (from opening the fuel
tank filler cap to completing the
refueling and closing the fuel tank
filler cap) must be performed by
the same person.
Other people may be carrying
static electricity. Do not allow
them to approach the fuel filler.
The person performing the
refueling procedure must not
return to the seat in the cab
part-way through the procedure.
(Continued)
Warning (Continued)
He/she could pick up another
charge of static electricity by
doing so.
Obey all cautions posted in filling
stations.
Type A
In the case of Type A, grip the tab of
the fuel tank filler cap when turning
the cap to open or close.