I can't work my laptop with my psu,I have tested it and it is giving out the right power,but my laptop will work on just battry power.I have tried to look for any obvious burns/blown components but can't see nothing,I know it must be a fuse or something,but don't know were or how to find it.can anyone tell me what I am looking for,I can get usage ov a test meter if that will help.
I have already tried to find any thing around the dc jack area the don't give any continuity,but all seem to be fine.can anyone give me some pointers on how to find this blown fuse or resistor.
Thanks

The adapter probably isn't. Voltage is OK when unloaded, but loaded it dies probably because the cord is compromised and is holding on by one strand. It normally breaks either near the plug that goes into the laptop or where it exits the brick.

You have to test the PSU under load. I'd use two 12 V light bulbs like a brake lamp wired in series and measure the voltage at the adapter.