<s>
A	O
tell-tale	B-General_Concept
,	O
sometimes	O
called	O
an	O
idiot	B-General_Concept
light	I-General_Concept
or	O
warning	O
light	O
,	O
is	O
an	O
indicator	O
of	O
malfunction	O
or	O
operation	O
of	O
a	O
system	O
,	O
indicated	O
by	O
a	O
binary	O
(	O
on/off	O
)	O
illuminated	O
light	O
,	O
symbol	O
or	O
text	O
legend	O
.	O
</s>
<s>
The	O
"	O
idiot	B-General_Concept
light	I-General_Concept
"	O
terminology	O
arises	O
from	O
popular	O
frustration	O
with	O
automakers	O
 '	O
use	O
of	O
lights	O
for	O
crucial	O
functions	O
which	O
could	O
previously	O
be	O
monitored	O
by	O
gauges	O
,	O
so	O
a	O
troublesome	O
condition	O
could	O
be	O
detected	O
and	O
corrected	O
early	O
.	O
</s>
<s>
Such	O
early	O
detection	O
of	O
problems	O
with	O
,	O
for	O
example	O
,	O
engine	O
temperature	O
or	O
oil	O
pressure	O
or	O
charging	B-Algorithm
system	I-Algorithm
operation	O
is	O
not	O
possible	O
via	O
an	O
idiot	B-General_Concept
light	I-General_Concept
,	O
which	O
lights	O
only	O
when	O
a	O
fault	O
has	O
already	O
occurred	O
–	O
thus	O
providing	O
no	O
advance	O
warnings	O
or	O
details	O
of	O
the	O
malfunction	O
's	O
extent	O
.	O
</s>
<s>
Automotive	O
tell-tales	B-General_Concept
are	O
regulated	O
by	O
automobile	O
safety	O
standards	O
worldwide	O
.	O
</s>
<s>
In	O
the	O
United	O
States	O
,	O
National	O
Highway	O
Traffic	O
Safety	O
Administration	O
Federal	O
Motor	O
Vehicle	O
Safety	O
Standard	O
101	O
includes	O
tell-tales	B-General_Concept
in	O
its	O
specifications	O
for	O
vehicle	O
controls	O
and	O
displays	O
.	O
</s>
<s>
In	O
Europe	O
and	O
throughout	O
most	O
of	O
the	O
rest	O
of	O
the	O
world	O
,	O
ECE	O
Regulations	O
specify	O
various	O
types	O
of	O
tell-tales	B-General_Concept
.	O
</s>
<s>
Different	O
tell-tales	B-General_Concept
can	O
convey	O
different	O
kinds	O
of	O
information	O
.	O
</s>
<s>
Colour	O
may	O
also	O
communicate	O
information	O
about	O
the	O
nature	O
of	O
the	O
tell-tale	B-General_Concept
,	O
for	O
example	O
red	O
may	O
signify	O
that	O
the	O
vehicle	O
cannot	O
continue	O
driving	O
(	O
e.g.	O
</s>
<s>
The	O
oil	O
pressure	O
idiot	B-General_Concept
light	I-General_Concept
lights	O
when	O
engine	O
oil	O
pressure	O
drops	O
below	O
a	O
predetermined	O
level	O
.	O
</s>
<s>
This	O
tell-tale	B-General_Concept
can	O
bear	O
the	O
legend	O
or	O
a	O
pictogram	O
of	O
an	O
oil	O
can	O
.	O
</s>
<s>
The	O
engine	O
temperature	O
tell-tale	B-General_Concept
is	O
usually	O
installed	O
singly	O
,	O
but	O
has	O
less	O
commonly	O
been	O
installed	O
in	O
pairs	O
.	O
</s>
<s>
A	O
"	O
malfunction	O
indicator	O
lamp	O
"	O
(	O
MIL	O
)	O
or	O
"	O
check	O
engine	O
light	O
"	O
(	O
CEL	O
)	O
illuminates	O
,	O
usually	O
in	O
red	O
,	O
amber	O
,	O
or	O
yellow	O
,	O
to	O
indicate	O
malfunction	O
or	O
a	O
service	O
requirement	O
detected	O
by	O
the	O
computerized	B-Device
engine	B-Device
management	I-Device
system	I-Device
.	O
</s>
<s>
Unlike	O
other	O
types	O
of	O
idiot	B-General_Concept
light	I-General_Concept
,	O
an	O
MIL	O
does	O
not	O
correspond	O
to	O
a	O
condition	O
that	O
would	O
have	O
been	O
read	O
out	O
on	O
a	O
gauge	O
.	O
</s>
<s>
An	O
idiot	B-General_Concept
light	I-General_Concept
can	O
indicate	O
that	O
the	O
vehicle	O
's	O
alternator	B-Algorithm
or	O
generator	O
is	O
not	O
properly	O
charging	O
the	O
battery	O
.	O
</s>
<s>
The	O
light	O
normally	O
appears	O
when	O
the	O
vehicle	O
ignition	O
is	O
turned	O
on	O
,	O
but	O
the	O
engine	O
is	O
not	O
running	O
,	O
as	O
it	O
detects	O
that	O
no	O
power	O
is	O
coming	O
from	O
the	O
alternator	B-Algorithm
(	O
the	O
alternator	B-Algorithm
is	O
powered	O
off	O
the	O
engine	O
so	O
only	O
generates	O
when	O
the	O
engine	O
is	O
running	O
)	O
.	O
</s>
<s>
It	O
subsequently	O
extinguishes	O
as	O
soon	O
as	O
the	O
engine	O
starts	O
and	O
the	O
alternator	B-Algorithm
starts	O
generating	O
electricity	O
.	O
</s>
<s>
Many	O
vehicles	O
have	O
a	O
red	O
tell-tale	B-General_Concept
to	O
indicate	O
that	O
the	O
parking	O
brake	O
is	O
engaged	O
or	O
that	O
there	O
is	O
a	O
fault	O
with	O
the	O
vehicle	O
's	O
braking	O
system	O
.	O
</s>
<s>
This	O
tell-tale	B-General_Concept
in	O
most	O
cases	O
bears	O
the	O
ISO	O
symbols	O
for	O
a	O
parking	O
brake	O
and	O
for	O
a	O
braking	O
system	O
emergency	O
.	O
</s>
<s>
In	O
the	O
past	O
,	O
US	O
regulations	O
required	O
this	O
tell-tale	B-General_Concept
to	O
bear	O
the	O
legend	O
.	O
</s>
<s>
As	O
a	O
cost-saving	O
measure	O
,	O
individual	O
readouts	O
for	O
each	O
tire	O
are	O
often	O
substituted	O
with	O
a	O
single	O
tell-tale	B-General_Concept
indicator	O
for	O
all	O
tires	O
.	O
</s>
<s>
Dashboard	O
indicator	O
lights	O
or	O
tell-tales	B-General_Concept
are	O
provided	O
for	O
turn	O
signals	O
,	O
high	O
beam	O
,	O
transmission	O
mode	O
in	O
automatic	O
transmission	O
vehicles	O
,	O
and	O
similar	O
devices	O
.	O
</s>
