Good place to start is your battery. It should have between 12.4-12.6 volts. Next check you brake light switch & then your crankshaft position sensor. If you have a code reader, scan for codes. There are also some fuses that should be checked if all the aforementioned items check out.
Been thought it. The Dealer wanted to change shift motor, transmission, and something else ($6800). Had it towed to friend's garage, he checked everything he could, not much technical data out there. He checked all wires & connectors. He said the computer not getting transmission position data. At this point giving up and selling, sad because engine runs great.