[Toutouxc]

Funny thing, I'm NOT colorblind and apparently I only rely on the color. I've been driving for over 10 years now, mostly in the capital that has traffic lights everywhere, and sitting at my desk now not looking at a traffic light, I wouldn't want to bet money on the order.

[city41]

I always assumed red was at the top as it's the most important. It's the first one to peak out behind tall trucks.

[bombcar]

Some places have the lights sideways, and usually red is on the left, but it's not always consistent.

If I were designing them I'd always have the red be noticeably larger.