Lighting Features; Entry Lighting; Exit Lighting; Battery Load Management - GMC Yukon 2021 Owner's Manual

Press the lens on each reading lamp to turn
it on or off.

Lighting Features

Entry Lighting

Some exterior lamps turn on briefly at
night, or in areas with limited lighting,
when is pressed on the remote key. After
about 30 seconds the exterior lamps turn off
when any door is opened, the unlock button
on the remote key is pressed, or when the
ignition is switched off. All interior lights
turn on and then the dome and remaining
interior lamps dim to off after 20 seconds.
Entry lighting feature for exterior lighting
can be changed by Vehicle Locator Lights.
See Vehicle Locator Lights under Vehicle
Personalization 0 125.

Exit Lighting

Some exterior lamps come on at night, or in
areas with limited lighting, when the driver
door is opened after the ignition is turned
off. The dome lamp comes on after the
ignition is turned off. The exterior lamps and
dome lamp remain on after the door is
closed for a set amount of time, then
automatically turn off.
The exterior lamps turn off immediately by
turning the exterior lamp control off.
The exit lighting for exterior lights can be
changed. See Vehicle Personalization 0 125.

Battery Load Management

The vehicle has Electric Power Management
(EPM), which estimates the battery's
temperature and state of charge. It then
adjusts the voltage for best performance
and extended life of the battery.
When the battery's state of charge is low,
the voltage is raised slightly to quickly bring
the charge back up. When the state of
charge is high, the voltage is lowered
slightly to prevent overcharging. The
voltmeter gauge or the voltage display on
the Driver Information Center (DIC),
Lighting
if equipped, may show the voltage moving
up or down. This is normal. If there is a
problem, an alert will be displayed.
The battery can be discharged at idle if the
electrical loads are very high. This is true for
all vehicles. This is because the generator
(alternator) may not be spinning fast
enough at idle to produce all the power that
is needed for very high electrical loads.
A high electrical load occurs when several of
the following are on, such as: headlamps,
high beams, fog lamps, rear window
defogger, climate control fan at high speed,
heated seats, engine cooling fans, trailer
loads, and loads plugged into accessory
power outlets.
EPM works to prevent excessive discharge of
the battery. It does this by balancing the
generator's output and the vehicle's
electrical needs. It can increase engine idle
speed to generate more power, whenever
needed. It can temporarily reduce the power
demands of some accessories.
Normally, these actions occur in steps or
levels, without being noticeable. In rare
cases at the highest levels of corrective
action, this action may be noticeable to the
driver. If so, a DIC message might be
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