plug in master cylender???

[Sdavne]

I have a 1990 300zx n/a 2+0 and i was looking around my master cylerder and i saw an opening there for a plug but could not see a plug laying around. long story short i found a wire behind a couple wires that i had to untangle to fit in and the plug fit in. i plugged in and did not see or feel any difference??/ anyon know what wire goes into the brake cylender??

[Q451990]

Probably feeds the "Brake" idiot light on your dash. On most Nissans the same light that comes on when your ebrake is set also comes on if your brake fluid runs low.

Heath

[Sdavne]

that would make sence but when i plugged it in nothing changed... the parking brake always worked but maybe it is for what u said when it gets low thanks