Hello,
I am a mechanical engineer and only learned the basics of electronics (by average got 2 hours/week lessons in electronics).
I have been busy with a dead playstation 4, eventually found the root cause and the solution.
Because it cost me maybe 6 hours, and I am questioning : Could I have done this faster ?
This is what I have done:
1) Replaced power supply by new one -> same problem, no reaction on power on button, nor eject button
2) Measured output lines of power supply, 5V, but when connecting it to motherboard, is goes down to 0V.
Concluded, there is a component defective, or there is a short circuit on the motherboard
3) Took my voltage regulator and connected it to 5V input on the motherboard, took 5V and 50mA to be safe.
What I did see, was that the Amperage on my PC screen was fluctuating from 0A up to 2A and I heared a vibrating (maybe 2kHz) sound from the motherboard.
I listened very carefully and discovered that the component RT5069A (Power Management Multi-Channel IC (PMIC)) was making the noise, took my IR temperature measurement pencil and measured 40 degrees Celcius. Much higher then all other components.
4) Desoldered the IC, put 5V with 50mA on the mobo and problem was gone. Did not hear the sound.
5) Replaced the IC by a new one -> same problem
6) Compared the motherboard with a good working motherboard and found out, that on 1 output line of the RT5069A IC , was connected to ground on the defective motherboard, and not connected to ground on the good working identical motherboard.
7) Then I measured on both sides of the motherboard, to which points, the output line was connected and marked them all. Totally there were about 39 points.
I did not measure under the BGA chips.
Then I checked if there were single components in between that point and ground. I was searching for single components which were defective and shorted.
There were about 30 of them, of the 39 points.
9) Then I measured (Fluke 175) the resistence of those single components and started to desolder the components with the lowest resistence.
Eventually after desoldering 5 components (and of course soldering it back), I found that a smd capacitor was shorted.
Replaced that one with an identical one, from a scrap board, and everything was working.
This is the first time I went that far, I am thinking about, could I have done this faster ?
Maybe with the right equipment ?
Kind regards,
Ed