Start button short

[spryDawg]

Hello. I've got a problem with my starter button shorting the electrical system. It's starts up fine when cold but clicks once and then shuts everything off when warm. I know my scoot pretty well (for a newb) and have been upgrading all the basics for a couple of years. 2015 Tao Tao 150cc kickstarts, idles and accelerates perfectly. All lights, wires, grounds, fuses, battery, and harnesses are in good working order. Starter and relay have been replaced and CDI, coil and plug are upgrades. Brakes and signals are fine. The starter button assembly has been inspected and it's housing is very clean. This scoot has never been wet. The only pre existing condition is an unresponsive tach which wasn't working long before the current issue and I've learned to live without it as wiring diagrams are not my strong suit. Thank you for any assistance.