Pontiac 2005 GTO - Manual (Page 120)

Charging System Light
The charging system light
will come on when you
turn on the ignition,
until the engine is started,
as a check to show
you it is working.
When the engine is running, the light should go out.
If the light illuminates and the Check Alternator message
on the trip computer stays on, or comes on while you
are driving you may have a problem with the electrical
charging system. It could indicate that you have a loose
generator drive belt or another electrical problem.
Have it checked right away. Driving while this light is on
could drain your battery.
If you must drive a short distance with the light on, be
certain to turn off all your accessories, such as the radio
and air conditioner.
The Check Alternator message will remain until the
MODE button on the trip computer is pressed, but the
symbol will remain until the problem is fixed.
One-to-Four Shift Light (Manual
Transmission)
When this light comes on,
you can only shift from
FIRST (1) to FOURTH (4)
instead of FIRST (1) to
SECOND (2).
You must complete the shift into FOURTH (4) to turn off
this feature. This helps you get the best possible fuel
economy.
After shifting to FOURTH (4), you may downshift to a
lower gear if you prefer.
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