my 88 4runner working one day now won't start and no lights etc. battery new.

if this is a side mounted battery connections i would check the neagitve cable to see if its loose at the battery. The negative side has less thread than the positive and gives out. i would check and or replace the negative side bolt about once ever 2 years ( dont over tighten as its very easy to strip). if its the standard top side battery cables i would check for loose connections there. also check the cables for corrossion on the inside where it meets the terminal. this is uassaully the problem.. take care. kffl :)

is the battery dead? can you start it with a jump? if so, could be your alternator but it sounds like some connections. start playing with the cables and see what you can find.

is it a standard ? what happens after you boost it