Starting Problems

Hey guys. Last night my wife was about to leave work in the LR3. She got out there and nothing was working. Not the key fob, non of the electrical, nothing. The lady she works for tried to help her jump it. Having it connected to her Yukon's battery was able to get the radio and information center on but would only click when she attempted to start. They let it set for a bit to try to get a charge and still nothing. They took the Yukon off and I came to her work to try and figure it out.

When I got there I immediately hooked it up to my trucks battery. This time nothing was coming on when I turned the key except for some lights flickering. Airbag light was flickering, and nav screen was flickering. I waited a minute, turned the key to on and put the car in reverse and back into park. This brought all systems up and I was able to start the car. Got it home, parked it, unloaded the newborn and his stuff and I went back out to try to start the LR3 on its own. Everything is fine, other than the information center flashed 'Service -12900' and then a second message 'Service -5000'

My initial thought was that the vehicle probably has a safety on it that wont allow it to start if it doesnt think it is in park. Not so sure anymore as this has happened 4 times now.

Any thoughts? Thanks.