a vtec light is any form of light source (LED, neon, etc) that is wired to the ECU so that when vtec is engaged, the light turns on.. it really has no benefits to it, just a cool mod to do if you're bored or something.. however, if it was me, i would just run a wire into the engine bay and tap the actual vtec solonoid wire.. i wouldnt wanna ƒuck up any of my ECU connections.

and no, it doesnt come stock on any cars that have vtec..

<[side note]>
its vtec. not v-tech, v-tec, vtek, or vtech.

Variable [Valve] Timing [& Lift] Electronic Control.. i dont see any Hs, Ks or dashes

VTEC or vtec