Buick RIVIERA 1993 Manual page 115

Engine Coolant Temperature Warning
Light and Gage
Malfunction Indicator Lamp (Service
Engine Soon Light)
the engine off as soon as
possible.
HOT COOLANT CAN BURN YOU BADLY!
In "Problems on the Road," this manual shows what to
do. See "Engine Overheating" in the Index.
A computer monitors operation of your fuel, ignition
and emission control systems. This light should come
when the ignition is on, but the engine is not running, as
a check to show you it is working. If it does not come on
at all, have it fixed right away. If it stays on, or it comes
on while you are driving, the computer is indicating that
you have a problem. You should take your vehicle in for
service soon.
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