Go to the trunk of the car, open it, left hand side in the rear of trunk there should be a cardboard cover over some connectors, find it and open it up.
Find a 6 cavity connector called C320 with a brown wire on one end, called cavity F if you can read it on the connector it should be printed in very tiny letters on one side or maybe both sides.
The brown wire is the tail lamp/parking lamp wire.
See if there's power on it when the headlamps or parking lamps are ON.