random electrical gremlins

I've got a 2008 Taco. Recently the turn directionals, backup lights, heater control switch, speedo/odo all died. The dash looks like a christmas tree with flashing engine light, air bag light, seat belt light, but interestingly, the buzzer doesn't work (yea!). I've unhooked, cleaned, reconnected the battery, and checked fuses. Also looked for obvious grounds. I'm mystified by the randomness of what doesn't work. Any ideas on what to look for/check next?

 

Check your windshield for leaks. A few years back, my '01 went nuts. Blinkers, horn, lights flashing, buzzing, clicking, the whole works. The shop said they had seen it once on a rav4. They put a hard spray of water on the windshield on the driver's side and some water (not much) started running onto the floor behind the dash. They put in a new windshield and ran the heat really high to help dry everything out and no problems since. Good luck.