here is the part that stops the outer tail lamps from working
circled in red
the area circled in red touches these contact points, which gives the LED power
on mine the contacts in the bulb holder were sort of corroded, and the circuit was intermittent
I used sandpaper and cleaned them all up
and also bent them upwards to so they would touch the contact points with more force, that worked initially
second time I got sick and tired of the LED going on and off
so I soldered a wire between the bulb holder and the tail light
now it works 100% of the time, forever