Anej Reja

Hi. When i was repairing my Yamaha DT 50, i removed a huge part of a bike to get to the carburetor. I did not touch almost any wiring, except removing the batery and detached 2 wires, that i later have attached again, when i was assembling the bike. When i assembled it my rear and headlight doesn't work. My horn and indicators work perfectly. What could it be?