Pontiac 2005 GTO - Manual (Page 215)

Cooling System
When you decide it is safe to lift the hood, here is what
you will see:
A. Radiator Pressure Cap
B. Electric Engine Cooling Fan
C. Engine Coolant Overflow Reservoir
{ CAUTION:
An electric engine cooling fan under the hood
can start up even when the engine is not
running and can injure you. Keep hands,
clothing and tools away from any underhood
electric fan.
If you can hear the coolant inside the coolant overflow
reservoir bubbling or boiling, do not do anything
else until it cools down. The vehicle should be parked
on a level surface.
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