DC voltage good at output? The PA-1700-02 ac adapter for your laptop ac adapter supply transforms and rectifies AC to DC. The ratings for the DC output are printed on the label, 15V at 4.0 A, 19.V at 2.0A, depends entirely on your model and the voltage of the battery used (the charging voltage has to be higher than the battery voltage). You can't play a mix and match game with laptop ac adapter, it has to be the right voltage and have the exact barrel connector (inside and outside diameter and overall length) on the power cord or it may cause damage or simply not work.
It's easy to check the PA-1700-02 ac adapter voltage with an autoranging VOM or for a manual range VOM, usually the 20V range for DC. While checking the laptop ac adapter voltage doesn't confirm that the transformer is sourcing the required current, it's not as tricky as checking laptop battery voltage where a surface charge can trick you into thinking a bad battery is good when no load is present. The voltage you read should be within 5% of the faceplate PA-1700-02 ac adapter voltages printed on the label. You can't confirm this by checking the DC plug with your tongue, and you may end up getting some spit in it that shorts out the whole works when you plug it back into the notebook.
If the pin is missing but your still getting intermittent power, it must be stuck inside the connector coming from the PA-1700-02 ac adapter and making contact with the broken part on the inside when it's plugged in tight. If the pin is loose to the touch, if it moves easily if nudge it with a pencil point or a toothpick, it's probably hanging on by a thread and responsible for intermittent or limited laptop ac adapter power. The ground contacts for the outside of the barrel can theoretically fail as well if it's a lousy design, but I haven't come across it yet. Replacing the connector inside the laptop, whether it's on the mainboard or on a special PA-1700-02 ac adapter power section board, is one of the most labor intensive repairs a relative newbie can hope to carry out successfully.