Doesn't your led headlight with H4 connector work correctly on high low beam or not lit at all after installation? It probably is the polarity problem.This happens because the Positive and Negative pole of your stock H4 headlight harness socket reversed with Led headlight.  Bellow image 1 is the polarity on H4 connecter of led headlight. And image 2 shows the condition which is making your led headlight not working. How to troubleshoot wether it is the mentioned polarity problem above or not? You can simply connect your led headlight according to above image 1 polarity drawing via using two wires with your car battery directly.  And see if the high low beam of led headlight work correctly. How to solve the polarity problem to make your H4 led headlight work normally? You can use our H4 to 3 pins wiring adapter to change polarity without cutting wires of your vehicles.Link to H4 to 3 pins adapter...