Black plate (37,1)Cadillac STS Owner Manual - 2011speed. For more battery saving information, see“Battery Saver Active Message” under DIC Warningsand Messages on page 4‑76.Electric Power ManagementThe vehicle has Electric Power Management (EPM) thatestimates the battery's temperature and state of charge.It then adjusts the voltage for best performance andextended life of the battery.When the battery's state of charge is low, the voltage israised slightly to quickly bring the charge back up.When the state of charge is high, the voltage is loweredslightly to prevent overcharging. If the vehicle has avoltmeter gauge or a voltage display on the DriverInformation Center (DIC), you may see the voltagemove 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 electricalloads are very high. This is true for all vehicles. This isbecause the generator (alternator) may not be spinningfast enough at idle to produce all the power that isneeded for very high electrical loads.A high electrical load occurs when several of thefollowing are on, such as: headlamps, high beams, foglamps, rear window defogger, climate control fan at highspeed, heated seats, engine cooling fans, trailer loads,and loads plugged into accessory power outlets.EPM works to prevent excessive discharge of thebattery. It does this by balancing the generator's outputand the vehicle's electrical needs. It can increaseengine idle speed to generate more power, wheneverneeded. It can temporarily reduce the power demandsof some accessories.Normally, these actions occur in steps or levels, withoutbeing noticeable. In rare cases at the highest levels ofcorrective action, this action may be noticeable to thedriver. If so, a Driver Information Center (DIC) messagemight be displayed, such as BATTERY SAVER ACTIVEor BATTERY VOLTAGE LOW. If this message isdisplayed, it is recommended that the driver reduce theelectrical loads as much as possible. See DIC Warningsand Messages on page 4‑76.Inadvertent Power Battery SaverThis feature is designed to protect the vehicle's batteryagainst drainage from the interior lamps, trunk lamp,glove box lamp, or the garage door opener. When theignition is turned off, the power to these features willautomatically turn off after 10 minutes (three minutes if anew car has 24 km (15 miles) or less). Power will berestored for an additional 10 minutes if any door isopened, the trunk is opened or the courtesy lamp switchis turned on.4-37
