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

https://signals.jovet.net/rules/UPRR%20Signal%20Rules.pdf

Arrow shaped warning boards are warnings of speeds coming up. Advance boards are supposed to have abwhite 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