tail lights - fast blink, all lit

I have a fast blinking left rear tail light, and a lit left front turn signal. i also had one bulb in the 3rd brake light out. the dealer said it was a problem with the ''board'in the third tail lite and i needed to replace it. I've done that, and the problem persists. I have changed the bulb and the socket in the front running/turn signal light...and it is always on, never blinks when turn signal is on. I am wondering if it's the rear tail light bulb is bad - but would not expect that to be true, since it is lit.
I will check the fuse next, but if that was blown, wouldn't expect the bulb to work. any ideas?

My last act will be to remove the tail light assembly, and replace the bulb in the tail light. It appears i need a special wrench to remove the pins that hold that assembly in place int he trunk.

Am I on the right track? any ideas what else I should pursue? Where might i find the special wrench for the pins in the trunk?
tks in advance.

the front turn signal sockets have been known to go bad too.

has it been this way since day 1? maybe it has a wrong bulb in it somewhere

the front turn signal sockets have been known to go bad too.

has it been this way since day 1? maybe it has a wrong bulb in it somewhere


Thanks....I've replaced one socket - perhaps I'll flip them (left--right, and vice versa, to see if the problem moves, and then order one if that's the case. Guess I could always return the high 3rd brake light assm....save me $120.
have a great day.

check the rear bulbs too. the rear assemblies come off by plastic wing nuts - maybe someone has stuck a single filament bulb in a double filament socket, or vice versa.