i have a e350 class c motorhome no headlights or turn singles
I would check the fuses and relays first. Pull the plugs to the head lights and see if you are getting 12 volts to the sockets with a test light. If no voltage, trace wires back and start looking for breaks or bad grounds. If blinkers and headlights are on the same switch, it could be the switch that is bad.
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