Pontiac 2004 Bonneville - Manual (Page 307)

Cooling System
When you decide it is safe to lift the hood, here is what
you will see:
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Electric Engine Cooling Fans
{ 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 recovery tank is boiling,
do not do anything else until it cools down. The
vehicle should be parked on a level surface.
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