Bare Conductive Paint cracks with with age causing it to become inconsistent in transmitting electrical currant.    

  An electronic trace made from CuPro conductive paint from LessEMF oxidizes over time, but it will still conduct current. Use a multimeter to test the trace for continuity then attach the power source to areas of paint that have not oxidized.     If the power source is attached to the oxidized areas the circuit will not activate.   […]