mac pro no powering up

[lukazmac]

hi. i have mac pro a1286 emc 2314. is not powering up. is anybody had problem with power supply? what normaly go faulty in this unit? i have 3 of them with this same problem

 

[dukefawks]

It's the back plane in most cases. There is zero documentation and I have never bothered to figure these out.