Engine Coolant Heater - GMC TopKick 2007 Owner's Manual

•
The charging system light should come on
when the ignition key is turned to RUN or
START and should go out when the engine is
running above idle. If the light does not go out
or comes back on during normal engine
operation, have the charging system checked
right away. (This light tells you if the generator
is not charging; it does not reflect the condition
of the battery.) See Charging System Light on
page 165 for more information.
•
The voltmeter charge indicator gage tells you
the condition of your battery's charge. The gage
should be in the center area during engine
operation. The red area on the left indicates an
undercharge condition; the red area on the right
indicates an overcharge. If the gage is in either
red area, have the battery and charging system
checked right away. See Voltmeter Gage on
page 166 for more information.
108
Notice: Do not allow the engine to operate at
low idle for more than five minutes. This
can cause low engine operating temperatures
which can affect engine operation and
reduce engine life. Engine idle speed should
be increased to 1200 rpm whenever extended
idle is required. Once started, the engine
should be placed under load to allow the
engine coolant temperature to reach 150°F
(66°C) before shutting off the engine.

Engine Coolant Heater

Your vehicle may be equipped with this feature.
In very cold weather, 0°F (–18°C) or colder,
the engine coolant heater can help. You will get
easier starting and better fuel economy during
engine warm-up. Usually, the coolant heater
should be plugged in a minimum of four hours
prior to starting your vehicle. At temperatures
above 32°F (0°C), use of the coolant heater is
not required.