Hi, this is about a 1st generation erista switch. Power button stopped working, all else was fine.
Made double and tripple sure, that button, cable, connector is all good and everything around the connector on the mainboard is fine.
Then I used board layer xrays to figure out power button signal is routed to the max77620 chip.
I actually found shorts around the chip - so yay (I thought).
Ordered new chip, removed chip, shorts still present (lesson learned, first desolder the caps).
Here’s a pic of my board.
cdn(dot)discordapp(dot)com/attachments/347047042956132362/906058013834633216/IMG_20211105_144851.jpg
sorry can’t put links or pics in my post.
All the red circled caps care shorted. moved the topmost one and the one below (in pic still in place) and they were in fact bad.
Qurstions:
What’s the calue of the circled components and the size?
It seems strange to me that all 5 of those caps went bad. Any idea if there could be another underlying problem? I’m worried if i replace them they might get blown again because of another problem.
Those aren’t caps, they are inductors, so are meant to have continuity across them. If they were bad, they would show OL, so these aren’t the issue. If it is just the power button that is bad, I doubt it would be something like the PMIC at fault. Were you able to boot it by plugging in the USBC cable?
I think your first step has to be getting the PMIC chip back on correctly.
Thanks for the info.
Seems like I made things worse then.
Yes, I was able to boot by plugging in the USBC cable.
I’ll try to revert everything then. Unfortunately one of the inductors was blown away by the hot air station into the nth dimension :(. Would you have a link where to order them?
Unfortunately I don’t have a donor board.
What else could be the issue for the power switch not working?
I don’t really… but I guess the obvious thing to try is test if pressing the power button shorts that point under the PMIC (or the nearby test point) to ground like it should. That will rule out a broken trace or bad switch / connector.