My Macbook Pro 13 Retina only charges (charger lights up and charges) if FIRST I plug the charger to the macbook THEN I join the metal part of the charger cable (see pictures).
If I do it the other way around: first join the metal part of the adapter cable and then plug it to the computer it doesn't charge.
A new Adapter doesn't work because of this reason (it has the metal part soldered from factory)
First I plug it to the laptop:
Then I join the metal part of the cable:
I'm not interested on fixing the charger, it won't work anyway as the problem seems to be the computer's Magsafe port.
Any ideas what the problem can be or how to fix it?
Can you explain me this behaviour?