Very similar to BNSF signalling but with different names for aspects.

Arrow shaped warning boards are warnings of speeds coming up. Advance boards are supposed to have a white box around the numerals. In the game, both advance and start of speed reduction signs are all yellow. Speed increase signs are green.

G
R  = clear
R

Y
G* = approach clear 60 - pass next signal at less than 60mph
R

Y
G  = approach clear 50 - pass next signal at less than 50mph
R

Y*
R = advance approach = pass next signal at 40mph or less
R

Y
Y = aproach diverging
R

Y
R = approach - next signal is stop - reduce to 30mph (40 for Amtrak and commuter trains)
R

Y  Y
L  R* = appoach restricting - next signal is restricted speed (15mph)
R  R

R   L  R R R* R  R
R      L R R  R* R = restricted speed
R        L R  R  R
NB

R R R
R R   = stop
R

Medium aspects don't mean the same thing as other signalling sysem. An aspect moved down one position means a diverge.

R
G* = diverging clear limited - speed through turnout less than 40mph
R

R
G = diverging clear - maintain prescribed speed through turnout
R


R
Y* = diverging advance approach -  diverge and not exceeding 40mph expect second signal at stop 
R

R
Y = diverging approach - diverge and not exceeding 30mph expect next signal at stop
R 

R
Y = diverging approach diverging - diverge then another diverge
Y