With the power completely disconnected, switch your digital multimeter (DMM) to or Resistance mode ( Ωcap omega ) . Place the black probe on a known chassis ground point.
Board powers up, indicator LED for +12V lights, but +5V logic is absent. No digital display activity. Mdk Mb-17 W Schematic
When repairing or building the MB-17 W, refer to these typical component values (verify against your specific PCB silkscreen): With the power completely disconnected, switch your digital