GMC 1994 Yukon Owner's Manual page 125

Service Throffie Soon Light
The orange Service
Throttle Soon light, if
you have one, is
located near the
middle left edge of the
instrument cluster
On diesel engines, a computer monitors the operation of the electronic
accelerator. This light should come on when the ignition is on but the engine
is not running, as a check to show you its working. If it does not come on at
all, have it fixed right away. If the light stays on after the engine starts or
comes on while you are driving, the computer is indicating that you have a
problem. You should take your vehicle in for service soon.
Glow Plugs Light
The orange Glow
Plugs light, if you
have one, is located
near the upper right
corner of the
instrument cluster.
If you have a diesel engine, it has a special starting system. An instrument
panel Glow Plugs light tells you when the engine is ready
to be
started. For
more details, see "Starting Your Diesel Engine" in the Index.
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