2013 Chevrolet Impala Owner Manual - Page 148

6-8 Lighting 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 Driver Information Center (DIC) message might be displayed, such as BATTERY SAVER ACTIVE. If this messages displays, it is recommended that the driver reduce the electrical loads as much as possible. See Driver Information Center (DIC) on page 5‑22. Battery Power Protection This feature helps prevent the battery from being drained, if the interior courtesy lamps, reading/map lamps, visor vanity lamps, or trunk lamp are accidentally left on. If any of these lamps are left on, they automatically turn off after 10 minutes, if the ignition is off. The lamps will not come back on again until one of the following occurs: . . The ignition is turned on. The exterior lamps control is turned off, then on again. The headlamps will time out after 10 minutes, if they are manually turned on with the ignition on or off.