Robot Odyssey Lock Puzzle

[Ben Sokal <fractal101@aol.com>]

I got past the sonic puzzle (It didn't seem too hard) and I'm now at
the 1973 Ford Pinto lock puzzle.  To solve it, I have to hit the starter
and than hit the buttons in the order : 1,3,2,4 Right?  
  But it's not working.  The gate doesn't open.  Do I have to do it for
more than one cycle or something?  Do I have to keep the robots pushing
the buttons and not de-press them until all of them are pushed?  I don't
get it.  Is it just a bug in my apple emulator that won't let the gate
open?  The buttons don't reset to their original color as if I had
messed up, the gate just won't open.  What is the solution to this
blasted puzzle?????                    Thanks, Ben