2013 Chevrolet Volt Owner Manual - Page 210

9-24 Driving and Operating The engine may run when Mountain Mode is selected, depending on high voltage battery charge, to build reserve battery charge for uphill climbs. If Mountain Mode is entered with a sufficient battery charge reserve, the battery charge reserve will appear grayed out and any battery charge reserve still unused upon exiting Mountain Mode will return to normal appearance. Press the Drive Mode button again to return to Normal Mode and it becomes active after three seconds. The Mountain light comes on when Mountain Mode is selected. See Mountain Mode Light on page 5‑22. Each time the vehicle is started, it will return to Normal Mode to maintain a smaller battery charge reserve for normal driving. provide better grade climbing performance. While driving in Mountain Mode, the vehicle will have less responsive acceleration. Mountain Mode will not change normal vehicle braking performance for steep downhill grades. See Hill and Mountain Roads on page 9‑9 and Electric Drive Unit on page 9‑28. Press the DRIVE MODE button to select Mountain Mode. If steep hill driving is expected, it is recommended to select Mountain Mode at least 20 minutes before driving on steep grades. This will allow the vehicle time to build a sufficient battery charge reserve. If Mountain Mode is not selected for these conditions, propulsion power may be reduced and the engine speed may increase. See Propulsion Power Messages on page 5‑49. Hold Mode Hold Mode is only available when the vehicle is in Electric Mode. This mode places the remaining battery charge into a reserve for the driver to use as desired. Selecting this mode transitions the vehicle to Extended Range Mode to maintain the battery charge reserve. Upon exiting Hold Mode, the reserved battery charge becomes available again and the vehicle returns to Electric Mode. If the transition is from Hold Mode directly to Mountain Mode, the electric range displayed adjusts for the Mountain Mode charge reserve.