GMC 1999 Sierra 1500 Pickup Owner's Manual page 149

GLOW PLUGS Light
I - -
GLOW
PLUGS
K2337
Your diesel engine has a special starting system. An instrument panel
GLOW
PLUGS light tells you when the engine is ready to be started. It is at the
upper right of your cluster. For more details, see "Starting Your Diesel
Engine" in the Index.
Low Coolant Warning Light
LOW
K2327
If you have a diesel engine, you have a low coolant warning light. If this light
comes on, your system is low on coolant and the engine may overheat. See
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