removing Li type headlight switch with VERY RUSTED screws?

[firekdp]

Correct. The ignition switch still controls the lights and the lower switch is still wired for indicators (thou they have been removed from the scoot).

Thought so from the position of the wiring on it, the purple on yours should be the wire to run directly to the horn. As it had indicators, was it a battery model? if so has the horn been changed for an AC type?

[vegansydney]

Thought so from the position of the wiring on it, the purple on yours should be the wire to run directly to the horn. As it had indicators, was it a battery model? if so has the horn been changed for an AC type?

The horn has been changed for a 12v AC one from SR. It works fine.

On your advice I unplugged the purple from the bulb holder and joined it to the white that exits the horn. Nothing.
This is one owner since new GP and was relatively untouched when I purchased it and the purple from the switch appears by length and bullet end connector that it should be going to the bulb holder.

However, if I earth the white that exits the horn it beeps (loudly too!). The problem with the LI3 type switch is it breaks the connection when the horn is pressed, so if I wire into the position where the purple currently is (see picture previous page) the horn will be permanently on until the button is pressed and circuit is broken.

Are the TV/SX/GP switches the same, in that they open the circuit when the horn is depressed?

Keen to wire this odd ball up with a working horn. Horn works but only when white that exits the horn is grounded. Any suggestions welcome!

[firekdp]

Are the TV/SX/GP switches the same, in that they open the circuit when the horn is depressed?

No, they all are push to make switches and as far as I know all Lambretta horn switches are the same ie push to connect.
I reckon that the switch is broken internally (possibly the copper strip has come away at the weld) so will have to come apart.