There are different light types like 'bluelight', 'special light', 'headlight' and 'breaklight'. The type 'bluelight' is normally used for emergency vehicles and those lights are ON for default (That's why they're flashing). 'Breaklight's aren't used in Emergency 3 and those are OFF for default. The lights of the vehicles on the freeplaymap don't have 'bluelights' but 'breaklights' (because 'breaklights' are off) A new command (called BluelightsOn) will turn those 'breaklights' on. You need find out everything else by yourself and use search function if you have more questions.