Small Engines (Lawn Mowers, etc.): Evinrude 50 hp outboard, electrical component, possibilty

Question
I have a friend, without use of the internet, who has an Evinrude 50 HP Outboard motor that will not shift into reverse, go into neutral properly or stay in neutral. It is equipped with electronic shift. How does he detemine the problem area and repair it? He is pretty handy with equipment.

Answer
KAREN, THIS PROBLEM IS INHERENT WITH THIS MODEL EVINRUDE ENGINE.  THERE ARE ELECTRICAL COMPONENT ON THE ENGINE THAT
MAKE THE SHIFTING F-N-R POSSIBLE.  WITHOUT BEING THERE MYSELF IT IS NEAR IMPOSSIBLE TO WALK SOMEONE THRU THE DIAGNOSTICS.  IF IT WERE ME I WOULD BITE THE BULLET AND TAKE
THE RIG TO A SHOP FOR DIAGNOSIS.  AT LEAST GET AN ESTIMATE
THEN DECIDE THE POSSIBILTY OF HOME TYPE REPAIRS.
GOOD LUCK
SINCERELY,
GEORGE