Chosen Solution
Hi Folks. PS4 working fine. Changed it’s location… and now it won’t turn on. Wall AC is good, AC power cord is good. Press power button, get a beep and a blue light for about 1 second… and that’s all. Won’t start in safe mode, either… no secondary beep. Tore unit down to test PS. Small connector from PS to Mobo: the two outer pins are +5VDC… middle two are ground and “start” Short “start” to +5v with a pair of fine tweezers, and as long as the short is maintained, the PS puts out +12VDC on the power rails. Remove the short, and the +12 begins to quickly decay to 0V. Question: should the PS continue to put out +12VDC after the short is removed, or does it need for the Mobo to “maintain the short” initiated by the power button press for the PS to continue to make +12VDC? Put another way: Take just the PC (remove the cable that connects it to the Mobo, so it’s just the PS on the table). Plug it into 110VAC. Now momentarily short (touch & release) the two pins that enable the PS to make +12VDC. They are labeled “ACIN DET” (I’m assuming this is AC input detect) and “ACDC STBY” (again, I assume AC & DC Standby) inside the PS. NOT connected to the motherboard, should the PS continue to make +12VDC, or does that “short” need to be maintained (presumably by the Mobo) in order to continue to make +12VDC? Until I can determine this, I can’t determine whether the problem lies with the PS itself, or if the fault lies somewhere in the Mobo. Don’t want to guess… want to know. Thanks for reading, and for any input!
Never mind… found the answer elsewhere. The PS makes +12VDC only when those two pins are ‘shorted.’ The Mobo does indeed ‘hold’ that short for as long as it’s “on”; when you shut it down, the Mobo shuts off the power supply. Thanks anyway.
Hello How did you solve? I also have the same problem .. could you help me? thanks max
