2001 X5, Bottom rear tail light replacement
 

So I tried replacing the bulb, and actually the original bulb in there, the filament was not even broken.

but the light doesnt work. i put in a new bulb (sylvania 7506(p21w) BP) and it still comes up 'rear light' error on the dash.

any ideas? i tried cleaning the metal parts (just brushing it with some saliva on my finger).

the original bulb has only one filament, not two like the higher brake light.

CHECK THE TAIL LIGHT IT SELF.THE CONTACT FOR THE BULB HOUSING BURNS AND IT WONT MAKE PROPER CONTACT

how do u chcek? i mean, what is the process and whta to look for?

This is common. "Check" meaning make sure is clean. Use some electric contact cleaner. I had the same problem on both sides and I haven't had any for quite a while now after I clean the the bulb housing.

can you be more specific? u mean on the removable piece or the pieces attached to the car?

bump

i had the same problem with my drivers side lower tail light. the socket that holds the light bulb completes the circuit when you twist it into the housing. you can see the metal tabs on the socket itself and the metal tab on the housing. the problem is when you twist the socket into the housing the metal tabs arent making a connection due to the corrosion on the housing in most cases. what i did was remove my taillight assembly so i could get better access. i then took a fine sand paper and gave the tabs on the housing a scuffing as well as the bulb socket itself. then when you twist the socket in it makes a proper connection. that was my easy fix and hopefully it is the same for you.

I also had a problem with my driver side tail light and when I pulled the bulb housing out I cleaned the contacts as well as bending them out slightly (before taking them out I could get the light to work by pressing on it gently on it to make a complete connection). I think from the age they were not as far out as they were when new and not making a complete connection. After I did that no problems whatsoever.