Signal / horn switch (applies to all E-trikes)
At the left hand grip we mount a custom enclosure that holds our DPDT-CO switch for turn signals and a momentary switch for the horn. These wires go to our lighting control unit. We will need it to be as small as possible with a handlebar clamp to secure it. The 5 wires from it along with wires from the Brake system need to travel along the handlebar and into the Lighting control box.
And there you have it, a custom signal switch with horn button. The last image says I am either going blind and can't measure right or was in too much of hurry to do a great job. What remains is to add the 5 wires, some rubber sealant, a few pop rivets and four tiny lid screws. You will note I also bent the metal the wrong direction so the horn button faces front instead of back which I hope it won't be a problem. For the horn you have your hand on the brake hand grip and can flip the signal with your thumb but instead of also being able to press the horn with your thumb, you have to press using your index finger.