Cadillac 2005 CTS - Manual (Page 192)

Turn off all unnecessary accessories to allow the battery
to recharge.
The normal battery voltage range is 11.5 to 15.5 volts.
You can monitor battery voltage on the DIC by pressing
the INFO button until you find BATTERY VOLTS.
Battery Voltage High
This message indicates that the electrical charging
system is overcharging the battery. When the system
detects that the battery voltage is above approximately
16 volts, this message will be displayed.
To reduce the charging overload, use the vehicle’s
accessories. Turn on the exterior lamps and radio, set
the climate control on AUTO and the fan speed on
the highest setting, and turn the rear window
defogger on.
The normal battery voltage range is 11.5 to 15.5 volts
when the engine is running. You can monitor battery
voltage on the DIC by pressing the INFO button until you
find BATTERY VOLTS.
Battery Voltage Low
This message will appear when the electrical system is
charging less than 10 volts or if the battery has been
drained.
If this message appears immediately after starting the
engine, it is possible that the generator can still recharge
the battery. The battery should recharge while driving
but may take a few hours to do so. Consider using
an auxiliary charger (be sure to follow the
manufacturer’s instructions) to boost the battery after
returning home or to a final destination.
If this message appears while driving or after starting
your vehicle and stays on, have it checked by your
GM dealer immediately to determine the cause of this
problem.
To help the generator recharge the battery quickly, you
can reduce the load on the electrical system by
turning off the accessories.
The normal battery voltage range is 11.5 to 15.5 volts.
You can monitor battery voltage on the DIC by pressing
the INFO button until you find BATTERY VOLTS.
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