You might be looking at your Laptop battery display noticing that the power level is getting gradually lower even though the Laptop Power Supply is plugged in securely. There is obviously a problem so what do you need to do to check before you go ahead and purchase a replacement? Firstly you need to check whether the fault is with the Laptop Charger or the laptop itself. You can test your laptop charger on a different machine or look to see if there is a power indicator LED somewhere on the body of the charger. If this is lit the adapter may be OK.
Another common fault could be with the charging socket in the laptop which may have been damaged. If you trip over your adapter it could jerk the charging port off the motherboard and stop the charging process. A professional repair will be needed to fix this. If you seem to have a dead Sony Laptop Charger then we can supply you with a replacement. Covering all models including the Sony Vaio Adapter the result will be a fully charging laptop in next to no time and a nice sum saved compared to shopping direct from the manufacturer.