FORD 2003 Explorer v.1 - Manual (Page 10)

WARNING LIGHTS AND CHIMES
Standard instrument cluster
Optional instrument cluster
Warning lights and gauges can alert you to a vehicle condition that may
become serious enough to cause expensive repairs. A warning light may
illuminate when a problem exists with one of your vehicle’s functions.
Many lights will illuminate when you start your vehicle to make sure the
bulb works. If any light remains on after starting the vehicle, have the
respective system inspected immediately.
Service engine soon: If this light
illuminates while driving, it is a
possible indication that one of the
engine’s emission control systems
has failed. SERVICE
ENGINE
SOON
Instrument Cluster
10