Lincoln 1997 Town Car Owner's Manual page 216

Working with the engine on:
1. Set the parking brake fully and make sure that
the gearshift is securely latched in P (Park).
2. Block the wheels. This will prevent your
vehicle from moving unexpectedly.
WARNING
Do not start your engine with the air
cleaner removed and do not remove it
while the engine is running.
WARNING
The cooling fan is automatic and may
come on at any time. Always disconnect
the negative terminal of the battery
before working near the fan.
214
If the battery is disconnected, the computer must
relearn its idle control. See Battery in the Index.
NOTE: The engine compartment light may be
switched on or off at the light assembly. The light
assembly is located on the hood on the driver's
side. To turn the light on, pull the switch toward
you; to turn it off, push it away from you. The
switch may remain in the on position at all times,
as the light will turn off when the hood is closed.