[hairyhandedfool]

They are 'Hazard Lights', they do show when the doors are open. On 319s (I can't really speak for 170s) they also allow drivers to see where certain 'faults' on the unit are.

Every passenger door on a Mk2/3/4 vehicle has a similar light (meaning there are normally two on each side), but only the Mk4s were built with them.

 

[hairyhandedfool]

QUOTE (Richard Johnson @ 3 Nov 2008, 11:52) <{POST_SNAPBACK}>....Can I presume from their purpose that they were/are always Amber/Orange?

kind regards

Richard

I think there are two styles of Hazard/Warning light. The older BR stock has the orange square type, the newer type is made out of LEDs and has found its way onto older stock but is on most post-BR built stock. This web page shows both types, although it is based on the class 156 units rather than the 170

As far as I know only one UK train type has Warning/Hazard lights that are not orange, and they have a special rule in the rulebook, although I can't remember exactly which module it is in, and it goes something like:

"If you see blue Hazard lights displayed on a train, ignore them."

The train in Question? - Royal Mail's Class 325 EMU.

I don't know the purpose of the blue lights.

(P.S. Nothing on the railway is ever amber! It is either yellow (Signals) or Orange (Hazard/Warning lights)

)