The harness is not wired that way but will work with mods before the harness. Before I had the harness I wired in a switch that connected two of the wires at the dimmer switch so I could run high and low beam together. It would work for about 30 seconds then shut everything off for a few seconds, I think the switch heated up. After putting in Ryans harness, I asked him about doing this. He said his harness would have no issues but I may see some possible heat problems in the sealed beam itself. I have not had any problems but have not run high and low together for more than 10 minutes or so. It does really light things up. So you need to take two of the wires at the dimmer (don't remember which ones) and wire them together with a switch. The switch just allows you to choose either "high" or "high/low".