T40 works off battery but not psu help

[xyz]

I have a t40 that works off the battery but doesnt work off the power supply nor does it charge off the psu.

I checked the main fuse near the dc socket it was blown and i replaced it and still the same what else if there to check ?

[Harryc]

With a voltmeter check for 16V and 4.5A output at the tip of the AC adapter plug.

[xyz]

Forgot to add the ac adapter works fine.
The failure is on the motherboard somewhere.

[xyz]

Update tried shorting the fuse area and it works.
Any one know the value of the fuse ?
Or am i ok just to short it out with a thin kynar wire.

[sktn77a]

Did you check the fuse again after you replaced it? I might have blown again as soon as you connected the AC adapter?

[Brad]

It appears that there may be a problem with the motherboard. The fuse shouldn't have failed for no reason.

Brad

[xyz]

It came to me with a blown fuse.
I have shorted the fuse out with very thin wire and it boots.
What is the value of the fuse and what can i use in its place.. or am i ok with very thing wire 30awg