2011 Chevrolet Volt Owner's Manual - Page 327

Driving and Operating 9-25 Electric Mode In Electric Mode, the vehicle does not use fuel or produce tailpipe emissions. During this primary mode, the vehicle is powered by electrical energy stored in the high voltage battery. The vehicle can operate in this mode until the battery has reached a low charge. There are some conditions when the battery charge is high enough to provide Electric Mode operation, but the engine still runs. They are: . . Extended Range Mode When the vehicle reaches the end of its electric range, it switches to Extended Range Mode (ERM). In this secondary mode, electricity is produced by the fuel‐powered engine. This secondary source of electric power extends the vehicle range. Operation will continue in ERM until the vehicle can be plugged in to recharge the high voltage battery and restore Electric Mode. The high voltage battery will continue to provide some power and work together with the engine to provide peak performance when it is required, such as driving up a steep incline or for high acceleration maneuvers. The battery will not be charged nor will electric vehicle range be restored by the engine. In either Electric Mode or Extended Range Mode, when the hood is open, the engine will run without turning off if the vehicle is on. The high voltage battery is neither charged nor discharged when this occurs. In either Electric Mode or Extended Range Mode, if there is a high voltage battery fault, the engine may run without turning off to generate needed electricity. The Malfunction Indicator Lamp will turn on. See Malfunction Indicator Lamp on page 5‑21. Cold ambient temperatures. Hot or cold high voltage battery temperatures. The hood being open or not completely closed and latched. Certain high voltage battery fault conditions. Engine Maintenance Mode or Fuel Maintenance Mode being run. . . .