Engine Coolant Heater - GMC 2005 T-Series Owner's Manual

•
The charging system light should come on when the
ignition key is turned to ON 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.)
•
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.
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. Your vehicle may also have an
internal thermostat in the plug end of the cord. This will
prevent operation of the engine coolant heater when
the temperature is at or above 0°F (−18°) as noted on
the cord.
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