I recently bought a used Prius 3, and it drives great, but I notice a problem with the headlights. When driving, the passenger front and rear headlights would occasionally turn off then back on again. Taking the car out of Eco Mode doesn't help. It happens randomly, regardless of there's a bump or not. I even got pulled over last night because my headlight was out (thankfully he didn't give me a ticket). This is getting REALLY annoying. How do I fix this?! Sorry if this is the wrong thread.
Not sure I understand yet, but are you saying the exterior lighting (headlight, parking lights, brakes?) on the right side - passenger side - of the vehicle are intermittent? I would guess some rodent action on the wiring harness somewhere or indeed a loose connector. Doesn't sound like a low 12 V battery problem, although any electrical gremlins point to that as a primary source. Unless you are handy with a continuity tester and have the vehicle wiring diagrams I would refer to competent mechanical authority.