How can I know if my power supply is faulty or not?

Ok. So couple of weeks before i got a issue with the 4 pin power wire from PSU to motherboard. I wiggled it a bit more and it got destroyed. I went to the repair shop to make it they fixed the wire somehow but After that I got the PS4 on and off issue. Then i asked the repairer he said he couldnot fix it . Its probably the power supply or the APU. But in my case I think its the PSU. So how can I know if my powersupply is faulty or not without putting it into another ps4 or whatsoever. I donot want to spend 50 bucks if the powersupply is alright. And if its not how can I fix the problem . It turns on for a second or two and shuts down .