i think the power supply on my xps gen 5 is dying

my system will initialy turn on and go through the boot for 5-15 sseconds, shut off then sound like its trying to start but just flashes an orange light instead and turns off. it wont turn on againt ill i disconnect it from the wall for like 10 seconds... is there anyway i can confirm a messed up psu? and if so can i get a replacement?