GMC 1993 Safari Owner's Manual page 118

Features & Controls
Engine Coolant Temperature Gage
Standard Cluster
Digital Cluster
PO643
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 if your engine is too hot.
HOT COOLANT CAN BURN YOU BADLY!
In "Problems on
the
Road," this manual shows what to do. See "Engine
Overheating" in the Index.
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