GMC duramax diesel 2016 Supplement Manual page 31

30 Driving and Operating
If the light does not go off, wait a
few seconds, then try starting the
engine again. See your dealer as
soon as you can for a starting
system check.
If the light comes on and then goes
off and you know the batteries are
charged, but the engine still will not
start, the vehicle needs service.
If the light does not come on when
the engine is cold, the vehicle
needs service.
If the batteries do not have enough
charge to start the engine, see
Battery in the owner manual.
Check that the correct engine oil
has been used and changed at
appropriate intervals. If the wrong oil
is used, the engine may be harder
to start.
Be sure you are using the proper
fuel for existing weather conditions.
See Fuel for Diesel Engines 0 47.
If the engine starts, runs a short
time, then stops, the vehicle needs
service.
Warning
Do not use gasoline or starting
aids, such as ether, in the air
intake. They could damage the
engine, which may not be
covered by the vehicle warranty.
They could also cause a fire,
which could cause serious
personal injury.
Engine Idle Variations
Under certain conditions the engine
idle speed can vary or be elevated.
Change in idle speed is normal and
does not indicate a problem. Normal
conditions that can raise idle speed
are low voltage, DPF regeneration,
air conditioning compressor loads,
and engine warmup. These speeds
can range from approximately 600
to 1000 rpm.
Elevated Idle
The engine has a cold temperature
high idle feature which elevates the
engine idle speed from base idle to
1050 to 1100 rpm for pickup models
or 1200 rpm for van models when
outside temperatures are below 0 °C
(32 °F), and the engine coolant
temperature is below 65 °C (150 °F).
This feature enhances heater
performance by raising the engine
coolant temperature faster.
To turn this feature on or off on
pickup models, see Vehicle
Personalization 0 26.
On van models, this feature can be
turned on and off using the DIC
buttons.
When the engine is started, it will
slowly ramp up to the high idle
speed after a delay of a few
seconds up to approximately
two minutes. For this method to
work properly there must be no
throttle or brake pedal faults.
The engine idle speed will return to
normal once the following conditions
are met:
Engine coolant temperature
reaches 65 °C (150 °F).
Air intake temperature reaches
0 °C (32 °F).