Electronics restarting while driving.

Hi All,

I recently got my engine replaced on a 1999 p38.
There are 2 weird things that i have noticed after the swap.
1. Random gearbox fault which stays for few seconds and disappears. Battery is new only 2months old. Amaron.
2. All electronics restarting while driving. The complete system except engine just shuts down and restarts again in few seconds. The trip meter resets also the radio.

Thanks for your help.