Ford 1997 Crown Victoria Manual page 21

The pointer moves from the C (cold) mark into
the normal band as your engine coolant warms
up. Under normal driving conditions, the pointer
should stay in the normal band. It is acceptable
for the pointer to fluctuate within the normal
band under normal driving conditions, and
under certain driving conditions such as, heavy
stop and go traffic, or driving up hills in hot
weather, for the pointer to indicate at the top of
the normal band.
If, under any circumstances, the pointer moves
above the normal band, the engine is
overheating and continued operation may cause
engine damage.
The engine coolant temperature gauge
If your engine overheats:
1. Pull off the road as soon as safely possible.
2. Turn off the engine.
3. Let the engine cool. DO NOT REMOVE
COOLANT SYSTEM FILL CAP UNTIL
THE ENGINE IS COOL.
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