With no power connected to the board put a meter across the inner barrel connector and Gnd. Should measure something 1Mohm, 2Mohm, very high resistance.
If you are seeing very low resistance, then there is good chances something is shorted.
With no power connected to the board put a meter across the inner barrel connector and Gnd. Should measure something 1Mohm, 2Mohm, very high resistance.
If you are seeing very low resistance, then there is good chances something is shorted.