> Why are separate light colors not mandated? They are mandated in any country that uses UNECE regulations for vehicle lighting. In the US and Canada, red tur

> Why are separate light colors not mandated? They are mandated in any country that uses UNECE regulations for vehicle lighting. In the US and Canada, red turn signals are allowed as a cost saving measure. That's why you can see high end luxury cars with LED tail lamp clusters that have red rear turn signals in the US.