Last Winter one of my headlights went out. After replacing it with a new one I noticed that
(1) the new headlight was weak
(2) the High beam didn't work

Today I decided to find out what was causing it.

It was the "Black ground" wire had broken from the connector to the headlights.
The Connector has clips in the back that you can release them with your finger nails. There you can access the wire connections in the connector.

My Fix, Since it is not a live wire (it has no power), I stripped the wire were it broke, I grabbed some aluminum foil making a wad around the exposed tip & stuffed it all into the connector where it used to attach, completing the ground circuit again. !!!!Never do this with the other wires!!! It would cause a FIRE!

Later I will solder the wire in place if it give trouble again.

Hope this helps others!

1999 Jeep Cherokee XJ 4.0L