TriggerFinger

if voltage is correct then it could mean your DC jack or the motherboard. if you know how to open it up, check your board for any burnt or shorted components. check also the DC jack if it is still soldered good on to the board. if it is not, try soldering it back. try also to reseat the connectors.

get hold of the service manual for your model (mostly from laptop's manufacturer website). use that as a guide when you disassemble your unit.

if every thing seem to be OK in your visual inspection and yet the problem remains, i suggest you take it to a repair shop for further analysis and troubleshooting.