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1. Embed this notice
   Geekman (geekman@bitbang.social)'s status on Tuesday, 07-Nov-2023 02:59:55 JST Geekman

   Having a painful time with the front panel situation for my G4 (AGP) motherboard. Neither of these parts work – reset and programmer buttons work as expected, however the LED and power button do not.

   When I examine voltages at the motherboard header, I see 3.3v signals where expected to power the LED and power-on button.

   However, when I test the board, both power buttons do not fully short, and when plugged in the voltage reads as ~2.5v.

   (🧵/1)

   • Embed this notice
     Mac84 ? (mac84tv@bitbang.social)'s status on Tuesday, 07-Nov-2023 02:59:53 JST Mac84 ?

     in reply to

     @Geekman I've never encountered this, but I would also be curious to inspect the voltages on the power supply. A lot of G4 systems have notorious PSUs, so you never know if this board may just be pushing things over the edge.

   • Embed this notice
     Geekman (geekman@bitbang.social)'s status on Tuesday, 07-Nov-2023 02:59:54 JST Geekman

     in reply to

     • Mac84 ?
     • Apple Product Collection

     Starting to suspect things based on what I've read online:

     1) The part is very unreliable – the boards floating around may be broken ones that were replaced under warranty

     2) The board is highly overwrought for some reason – voltages including the sleep throbber are controlled by the motherboard, so why on earth is there both an IC and crystal?

     3) To get the default behaviour I might just have to remove components and bodge around them.

     @mac84tv @applepc – Have you encountered this? (🧵/3)

   • Embed this notice
     Geekman (geekman@bitbang.social)'s status on Tuesday, 07-Nov-2023 02:59:55 JST Geekman

     in reply to

     This is very confusing since everything I read indicates these are the correct parts. Are these boards just unreliable? Is there a repair that needs doing?

     (🧵/2)

   • Embed this notice
     Geekman (geekman@bitbang.social)'s status on Tuesday, 07-Nov-2023 03:09:12 JST Geekman

     in reply to

     • Mac84 ?

     @mac84tv Hey! I don't have a vintage PSU, so I'm using a modern ATX supply with an adapter cable (based on xlr8yourmac's well-documented solution). Voltages on the PSU all look good.

     I can boot the Mac by shorting the appropriate pins on the panel header (3 power-on to 7 ground). I just need a button, but the board doesn't want be that! Measuring the continuity of the corresponding pins on the panel board, the power button has resistance when pressed – enough not to work.

     Perplexing!