GMC Terrain: 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 of the power 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 displayed and it is recommended that the driver reduce the electrical loads as much as possible. See Battery Voltage and Charging Messages on page 5‑26.
Entry Lighting
The dome lamp, cargo lamp, and foot lamp inside the vehicle come on when any door is opened, if the dome lamp is in the door position. In addition, these lamps come on when the Remote Keyless Entr ...See also:
High-mounted rear stop light
In addition to the lower-mounted rear stoplights
on either side of the car, the high mounted rear
stoplight in the center of the rear window also
lights when the brakes are applied. ...
Automatic Dimming Mirror — If Equipped
This mirror automatically adjusts for headlight glare
from vehicles behind you. You can turn the feature on or
off by pressing the button at the base of the mirror.Alight
to the left of the butt ...