I started the car tonight, and all the lights are flashing, headlights, dash lights, map lights, everything. It stays solid if I push in the brake, or turn the ac on. The car runs fine other than the lights flashing. I'm guessing theres a loose connection on the battery or something? Any help is appreciated.

 

there's a slight chance by your description that the alternator is on its way out. but this sounds more likely to be a grounding issue. i suggest you get a negative terminal clamp for your ground wire. with time, corrosion will expand between the terminal clamp and ground wire causing the connection to get weaker and weaker. try this out, should only cost you $1 and 20mins of your time.