BN C636 4366Portland OR Portland

Do these lights above the number boards have any function?

@RL Yes, these are known as Class Lights, meaning the class of the train being pulled. White class lights indicate a train which is an unscheduled Extra. Green class lights are used when a scheduled train has more than one section (another train or trains following under the same symbol). The Red lights are actually just marker lights in case the train has to make an unscheduled stop. They are not very bright, so one wonders if they were ever very effective as markers. Freight railroads in the US do not use class lights anymore, since there are no longer any scheduled freight trains listed in timetables. All freights are now run as Extra trains by default. Most US locos have had their class lights completely removed, or were never built with them if constructed beyond the mid 80's. In the photo above, the white lights are on, but just barely noticeable in the bright sunlight. Thanks for your comment!

Ok, thanks, I think I got it!

http://trainspo.com/photo/55103/
http://trainspo.com/photo/50182/
http://trainspo.com/photo/55792/
so these marking lights in above links are also class lights, but can change their colour if needed?

@RL Yes, there is a small lever at the bottom of the light which can be adjusted to show white, green or red.

Here in Estonia the system is a bit different. We have two types of lights on our locomotives. There is one headlight for illuminating the road and two ditch lights for ‪indication‬. If both ditch lights are lit, then locomotive is in “train mode”, e.g. going from point A to point B. If only one ditch light is lit, then locomotive is performing some sort of maneuvering works, in yards for example. One red ditch light indicates the rear end of locomotive (only in “train mode”, for maneuvering works there is one white ditch light on both ends). Note that ditch lights here are used only for indication, thus they are quite dim and not ment to illuminate the road. There are two examples for you:
http://trainspo.com/photo/62494/
http://trainspo.com/photo/31436/
This system is used anywhere over ex soviet countries using 1520/1524mm gauge railways.

Very good picture...!!!

@RL Thanks, that's good information. I have noticed the "one on - one off" ditch lights in the past and just thought one of them must be burned out. It happens over here occasionally, but it has no significance for the purpose of signalling a train's class. @Falk Thank you!