Pontiac 2004 GTO - Manual (Page 221)

Cooling System
When you decide it’s safe to lift the hood, you’ll see the
electric engine cooling fan (A) and the engine coolant
reservoir (B).
{ 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 the coolant inside the coolant surge tank is boiling,
don’t do anything else until it cools down. The vehicle
should be parked on a level surface.
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