VR5 automatic, shifting trouble/not start

[Domi84]

Got a call from my brother last night. His passat started to act weird after he drove it for 10 minutes. While shifting, the auto gearbox goes into neutral and stays there for a second or even more. The engine even revved into the limiter once. Got home 5 minutes later and parked the car.
An hour later, he wants to check if the problems is still there and the car is does not start at all.
I had his car on sunday and monday and nothing like this happend while i had it. Drove it for 800km(600mi). two times a four hour drive and some site seeing at location where the gearbox did his work without any problem.

Any ideas so far? The car is stock except for aftermarket hid's which are installed 5 weeks ago. Also, yesterday, before he started to drive. He installed some led lights in the headlights to match those hids. Could this cause some problems? He removed them anyway when the problem occured. Would be very akward.

I searched the forums. He is already gonna check the fluids and read codes. can't find anything else on the forums. maybe someone has any ideas?