Ford 2013 C-Max Full Hybrid Owner's Manual page 182

182 Unique Driving Characteristics
Frequently Asked Questions
Question
What are the series of clicks from
the cargo area when I first turn
the key in the ignition?
Why does the engine sometimes
start at key-on?
Why does it take a long time
before the engine shuts down?
2013 C-Max Full Hybrid (34h)
Owners Guide gf, 1st Printing
USA (fus)
Answer
The high voltage battery is
electrically isolated from the rest
of the vehicle when the key is off.
When the key is turned to on, high
voltage contactors inside the
battery are closed to make the
electricity available to the
motor/generator and enable the
vehicle to drive. The clicks are the
sound of these contactors as they
close and open during start up and
shut down.
The vehicle's computer will
determine if an engine start is
required at key-on. Silent key start
will start the engine if it is
necessary for cabin heating,
windshield defrost, or if the
outside temperature is low. (For
C-MAX Energi vehicles, engine on
is not required to operate these
functions.)
There are several reasons the
engine stays on for an extended
amount of time when it is first
started. One common reason is to
ensure that the emissions
components are warm enough to
minimize tailpipe emissions. As the
climate gets cooler, this engine-on
time is extended.