Ax1500i issue with 14 pin part of 24 power ate plug

Hello all,

My system shut down on me and would not start up again with the self test light on psu showing permanent red. I removed all cables from psu and pressed the self test button and it light up green with fan spinning. I then individually plugged in every cable separately and tried the self test, all worked with a green light until I came too the 14 pin part of the 24 pin. When I plug that in I hear a click and the self test does not light up or the fan doesn’t spin. Just as a note when I had cables connected to psu for testing I did not have the attached to motherboard.

Edit.

Just too add after some more plugging in plugging out, the 24 pin atx cable that plugs into the psu is made up of a 10 pin and a 14 pin part. If I plug the parts in separately I get a green self test light for each cable, however if plug them in together the self test does not give any signals neither light red or green or fan spinning.

I am at a loss as to what is causing this. There are no signs or smells of burning or excessive heat from system while I was using it. I do not want to open up the psu as the warranty stickers are still on and intact.

Model number is 75-001971

I would be great full for any tips or trouble shooting methods.

Kind regards

Benny