Frankied37

hey guys new to the forum here but I am restoring an 1976 cutlass supreme and I am trying to figure out why I don't have any working lights for the licensee plate, every other light is working in the car. I did check the voltage in the trunk and I did get about 4v at one of the terminals and thought that was low, just not sure what to look at next.


Thanks, Frank

Fun71

Check the ground for the license plate lamps. Since you measured 4 Volts it sounds as if the wires are connected but there is a voltage drop somewhere. Could be a poor ground between the socket and the body/chassis.

Frankied37

where can I find the ground for the license plate bulbs?

joe_padavano

If you are only seeing 4V on the hot side, the problem is not the ground. The problem is that you have a loose, dirty, or improperly crimped connector someplace. The most likely candidate is the splice in the harness in the trunk where the license plate light feed splits off of the wire to the tail lights.

Frankied37

so seems like I had the bad ground yesterday on my voltmeter, now reading 12v at the brown wire and 0v on the green, I went ahead and tapped the light gr into 12v and presto I had lights! so what role does the green wire play? since its separate from the brown 12v and ran all the way from the front of the vehicle. thanks for all the help guys

Yellowstatue

The brown wire is the licence light, the tan wire is fuel gauge and the green wire the back-up light.