It seems like the power jack on your laptop may be faulty. Pin 1 - SLEEVE TERMINAL, Pin 2 - SHUNT TERMINAL and Pin 3 - TIP TERMINAL 2. The first 4 pins on your board read 19.4~ V, the 5th pin is empty and the remaining 4 pins are connected land. It's possible that the SHUNT terminal is not working correctly and this could be causing the problem....