operators_manual

Table Of Contents
Check Engine Lamp - Turns on when a
problem exists, but the vehicle can still be
safely driven. Vehicle should be serviced to
correct the problem but the situation should
not be considered an emergency.
The lamp will also illuminate when a DPF
regeneration or addition of diesel exhaust
fluid (DEF) is required. For PACCAR PX
Engines, this icon may also illuminate if the
crankcase breather element needs
attention. Another function of the check
engine lamp is to warn the operator of an
impending idle shutdown. When the idle
shutdown timer is 30 seconds from
expiring, the ECM begins flashing the
check engine warning lamp once per
second. When the timer expires, the ECM
will turn off the warning lamp and shut
down the engine.
Engine is Overheating
The cooling system may overheat if the
coolant level is below normal or if there is
sudden loss of coolant. Follow these steps
if the engine is overheating.
CAUTION
The cooling system may overheat if
the engine coolant is at the minimum
level. A sudden loss of coolant,
caused by a split hose or broken hose
clamp could also lead to an overheat
condition. Always inspect to ensure
hoses and clamps are not cracked,
worn, or loose. Failure to comply may
result in equipment or property dam-
age.
NOTE
The system may also temporarily over-
heat during severe operating condi-
tions such as:
Climbing a hill on a hot day
Stopping after high-speed/high-
load driving
Debris blocking air flow through
the cooling module (radiator)
If the engine coolant temperature warning
lamp comes on and the audible alarm
sounds showing an overheat condition, or
if you have any other reason to suspect the
engine may be overheating, DO NOT
TURN OFF THE ENGINE unless a low
water warning device indicates a loss of
coolant. Follow these steps:
Follow these steps if the engine coolant
temperature is rising, or the temperature is
already above normal, and there are no
other warning alarms displayed in the
instrument cluster.
1. Reduce engine speed, or stop. When
stopped, place the transmission in
neutral (N) and set the parking brake.
Keep the engine running. See the
vehicle operator's manual for
instructions on transmission shifting
and parking brake information.
ENGINE OPERATION - Emergency - What To Do If
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