See also:

Ending a Call
Press to end a call. ...

Jump Starting (On-board with eAssist Only)
If the vehicle fails to crank, it may be jump started by using the eAssist battery to charge the 12-volt battery. Use the following procedure to activate the on-board jump start using the DIC ...

System stays in background
While I only got to drive the 2012 LaCrosse for a little over an hour, I was impressed at how utterly unimpressive the eAssist was. Everything works in the background. There's no electric motor wh ...