I was driving down the interstate (1996 camry 2.2) and lost all power, no head lights ,no engine, no brake lights. I pulled over and started swapping under hood relays and all power returned drove home no problems. now i realize the under hood relays did'n have anything to do with it, because I tried to recreate the total loss of power by removing relays with engine running and head lights on. still running fine no problems, Yet! Ok what could cause total power loss and return of power?