Traffic light Semaphore help?

Hello, some time ago, I tried to create a traffic light system 2 months ago, but I failed miserably, I ended up giving up. Maybe someone here knows how to solve this problem please?

that was all I tried in .blend
SistemSemaphore.blend (1.5 MB)

I need the vehicle to collide with the Blue stripe, reduce the speed and stop at the Red stripe. as shown in the picture

I also recorded this video playing Euro Truck Simulator How it should work: https://youtu.be/MpYm1_UR9f8
In the video the cars slow down and stop