1994 GMC Suburban 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. 2-69