Modern Vespa

Hi All ,
Does anyone know if the battery is necessary to have the tailight on a P125 in working order? I have been slowly working an a P project - got it running good -newly rebuilt engine - but the tailight and brake light does not come on. headlight works fine . i also do not have the key switch hooked up yet. It has a battery in it - its just pretty shot and won't hold a charge any more...

Any ideas what might be wrong and/or where to start looking ?

Thx~

The brake light will work when the engine is running. The tailight needs the battery to work. DOT thing.

The brake light and taillight run off the battery and headlight runs off the stator. Even if you have the battery installed, you don't have the switch installed so the battery current will never make it to the rest of the harness to run any lights other than the headlight which doesn't run through the switch.

So Matt - is it possible to hook up the wires necessary to get the tail light going in my headset without the switch ?
Do you know which wires need to be connected to have a work around til i can get a switch ?

thx

red and the large white.