Toyota RAV4 stalls- almost

yaks

twice, months apart, my Rav 4 has lost power while driving 70mph. at 1st I felt loss of power then all lights, check engine, air bag, oil, etc. illuminated & I thought car had stalled. I then began to pull over to side of road when just as suddenly all lights went out & power was restored. car reads no codes, run rough at times other times run fine. i am afraid that i will find myself straned at some point. does anyone know what is causing this problem?