Nakamichi ta-4a no power light at all. Dims out

Have few of these receivers some for parts some working
Recently picked one up with no power issue
It actually powered up for a minute then just blanked . Played music for few min. But once turned off it would not power back on
After sitting around for few days I tried to power it on. The Orange power light came on blinked once and then dimmed

I cleaned the power switch it definitely works. Checked with multimeter

What could be the cause?

I have few other ta-4a where I can borrow transformer and other parts