This DIY is for ANY 9nth Generation Corolla
When you have checked the bulbs and the wires in the elbow of the trunk .
I don't know why mine was missing a piece but as I did for the trunk light I traced my rear back up light wire to this opened end box .
You have to pull down the driver side carpet to find this junction of wires .
As you can see the 3 wires are connected to get the both back up lights to work .
The bottom 2 wires are for the trunk light which I do have another DIY on it .
These are many angles of how it should look - I don't know what was missing but if I go to a junk yard I will look for this piece .
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