overheating, engine light and on board computer problems on 2006 BMW 530i

sequence of events:
1. battery died from lack of use. After recharging engine light stays on. indicates overdue maintenance on 3 items filters and oil)
3.I can't check oil on computer. display, stays lit fully up regardles of engine running or not. overheats radiator fan works ok. I can lower temperature by running interior heater on max.

Asked by for the 2006 BMW 530i