License plate light 71 malibu
 

Having trouble getting the license plate light to work.(once installed) The bulb is new and works. I have all other lighting working properly. I tested the light on the battery by touching the single wire+ and then touching the light metal at the same time -. Is there any easy fix? I have a new chrome bumper on it, so I assume the ground is good. Just no power to the light when I put on the parking lights? I am hoping it is an easy fix... Thanks in advance. I just want everything working now that I'm almost ready to drive it down the road.

Using a good ground not on your new bumper, you should be able to use a meter or test probe and determine If you have 12v at the lamp socket.
If you have 12v then it’s a grounding issue with the mounting of your new bumper.
If you don’t have 12v, you’ll need to trace that wire back.