Typo Correction: The title should be Mase Ecospeed Tail & Brake Light Connections
The wiring diagram that you attached shows a two-wire rear light instead of a three-wire rear light so it is not much help. It also does not indicate what the wire colors are.
Unfortunately, I do not have a definite answer regarding which wires go where on the lamp holder.
My best guess is that T, S, and G are possibly Tail, Stop, and Ground. Black is the universal color for ground so chances are that black wire is ground and the remaining wires are for the tail and stop lights.
I have a 20 yr.old Mase Ecospeed Electric Scooter made by Mase Generators of Italy in the mid-1990s. It has a Hi-Lo beam headlight, a horn, and a CEV tail light with a 4W and 10W bulb (tail light and brake light). There are no turn signal lights.
I disconnected the tail light wires to access and replace the two 12V batteries and didn't mark the wires so now I don't know how to hook them back up. There are 3 wires with connectors coming from the scooter - purple, black, and red with black stripe. The purple wire has a different looking connector than the other two. The back of the CEV tail light has 3 connection points marked T, S, and G (possibly Tail, Stop, Ground??) along with numbers. The wiring diagram is in black and white.
I'm hoping you can tell me how to connect these 3 wires to the tail light to get it working again.
I've attached photos of the wiring diagram, the scooter wires that were attached to the tail light, the back of the CEV tail light, the light/horn switch and it's wiring.
I can take and send more pictures if you need them. Thank you for any help you can give me.