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 thedriver. If so, a Driver Information Center (DIC) message
might be displayed, such as BATTERY SAVER ACTIVE,
BATTERY VOLTAGE LOW, or LOW BATTERY. If this
message is displayed, it is recommended that the driver
reduce the electrical loads as much as possible. SeeDIC
Warnings and Messages on page 3-49.
Battery Run-Down Protection
The vehicle has a battery saver feature designed to
protect the vehicle’s battery.
When any interior lamp is left on and the ignition
is turned off, the battery rundown protection system
will automatically turn the lamp off after 20 minutes.
This will avoid draining the battery. This vehicle also
has a retained accessory power feature. If the radio
is on, it will turn off after 10 minutes or if any door on the
vehicle is opened. SeeRetained Accessory Power (RAP)
on page 2-21.
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