Wiring to tail lights

[mxrrss]

I'm kind of just going out on a limb with this one but does anyone happen to recognize/have any info on this black box? When I first got the car it would give a right/left tail lamp malfunction every time I started it, then one day it was locked and the battery died and I couldn't get into it and have to have a lockout person come to get into it. So after that happened I figured it was something to do with my battery so I bought a new one then when I went to change it I saw that little black box hooked up to both tail lights. I didn't mess with it because I had no idea what it was but I changed the battery and it didn't fix anything. (this was before I learned in BMW's you have to register the battery to the car) so I took it to BMW. I let them know about the black box just in case they knew anything about it, then when I went to get the car they one of the previous owners must have wired it in and said they didn't mess with it either because they also had no clue what it was. After I picked it up though it didn't give the malfunction error anymore so I just forgot about it. That was in May, then I wanna say around August it started giving the error again but it was random and wasn't every time like before. But a month later, now, it's giving the malfunction error again every time I start it.

[amrazM]

what year is your car?

[amg6975]

Looks like it has bulbs in it? I bet someone replaced the tail lights or tail light bulbs with LEDs and this is just a load to trick the car into thinking it has regular bulbs. I'd remove it, clean the wiring up back to stock and put normal stock bulbs in it.