68kMLA Classic Interface

This is a version of the 68kMLA forums for viewing on your favorite old mac. Visitors on modern platforms may prefer the main site.

Click here to select a new forum.
TiBook certain keys not working
Posted by: s_pupp on 2020-11-10 07:10:01
I have a PowerBook G4 500 (M5884) that is having a logic board keyboard issue.

The tab, command, left arrow, up arrow, and delete keys (and probably some others) do not work.

I have tried multiple keyboards, and all work normally with a different PowerBook G4.

I have tried heating the logic board connector leads after application of flux.  The pads and leads look great, but no difference.

Any suggestions?

Thanks in advance.

Posted by: s_pupp on 2020-11-14 14:43:00
Solved - bad PMU or PMU cable.

I replaced the logic board, but the problem remained.

I replaced the PMU board and PMU cable, and all the keyboards now work.

In this model, the trackpad connects to the PMU board.  The PMU board connector leads from the logic board to both the PMU board and the inverter.

How this affects the keyboard, which has its own connector, is beyond my ability to reason.

Too bad for me, all the futzing around with the logic board connector of the first motherboard resulted in a broken pin on what turned out to be a perfectly good 500MHz M5884 logic board.

1