2013 Chevrolet Impala Owner Manual - Page 147

Lighting 6-7 Delayed Exit Lighting This feature illuminates the interior for a period of time after the key is removed from the ignition. The ignition must be off for delayed exit lighting to work. When the key is removed, interior illumination activates and remains on until one of the following occurs: . . Parade Dimming Parade mode automatically prohibits the dimming of the instrument panel displays during the daylight while the headlamps are on so that the displays are still able to be seen. Battery Load Management The vehicle has Electric Power Management (EPM) that 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. If the vehicle has a voltmeter gauge or a voltage display on the Driver Information Center (DIC), you may see the voltage move 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. The ignition is in ON/RUN. The power door locks are activated. An illumination period of 20 seconds has elapsed. . If during the illumination period a door is opened, the timed illumination period will be canceled and the interior lamps will remain on because a door is open.