My XJ headlights were working quite well. All of a sudden, the low beam lights stopped working but the High Beam Headlights are working just fine. After some online research, I replaced the dimmer switch with a new one. The fault still exists..... Low beam headlights are still not working......Anyone knows what/where the fault could be ????

 

With the headlights turned on low beam start at the headlight and trace the voltage back to the point where it has been lost. IF when you test the voltage at the headlight there is 12 volts, you have a bad ground.

 

99.9% of all the electrical problems I have EVER had working on a car, truck, jeep, or bike, have been either a switch gone bad, or a ground wore out. If it ain't the switch....

 

Behind the left headlamp and near the air cleaner box is a connection that sometimes gets wonky. Unplug it, spray it out with electronics cleaner and plug it back in.

Also, in the same general area is a ground cluster mounted high on the driver's side inner fender. That screw can come loose and/or there is corrosion under the terminal rings.