Chevrolet 1994 Astro Passenger Owner's Manual page 123

NOTICE:
Damage to your engine from neglected oil problems can be
costly and is not covered by your warranty.
Engine Coolant Temperature Gage
Standard Cluster
If you have the Standard Cluster, you have a gage that shows the engine
coolant temperature.
If the
gage pointer moves to the "H" (red) side, your
engine is too hot!
It means that your engine coolant has overheated. If you have been
operating your vehicle under normal driving conditions, you should pull
off
the
road, stop your vehicle and turn
off
the engine as soon as possible.
If you have a digital cluster, a box around the temperature symbol will also
flash when your engine is too hot.
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