Using The Engine Block Heater - Ford 2001 Mercury Cougar Owner's Manual

USING THE ENGINE BLOCK
HEATER (IF EQUIPPED)
An engine block heater warms the
engine coolant, which improves
starting, warms up the engine
faster and allows the
heater defroster system to respond
quickly. It is strongly recommended
if you live in a region where
temperatures reach -23ºC (-10ºF)
or below.
For best results, plug the heater in
at least three hours before starting
the vehicle. Using the heater for
more than three hours will not
harm the engine, so the heater can
be plugged in the night before
starting the vehicle.
To prevent electrical shock,
do not use your heater with
ungrounded electrical systems or
two pronged (cheater) adapters.
Starting