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8 Keyboard & Track Pad Odd Behavior
Power Button ✔️ Caps Lock ✔️ Track pad Movement. ✔️ I can perform a PRAM reset (Opt+Cmd+P+R) ✔️ Function keys all OK ✔️
Powers on OK, I arrive at the set up to screen (High Sierra) and no keys are responding exceptthe function keys & there is no click function from the track pad but the cursor is moving. Connections are clean & cables are undamaged & fully seated & latched. The volume, KB backlight level indicator & the display brightness indicator the level bar is in reverse (Black 1st white 2nd)! weird.
Everything 'Was' working before..... Track pad has been swapped out 3x with no difference in actions. Whats going on?
We have replaced the LCD connector which was damaged with a 2012 LCD connector on a 2011 A1278 and replaced the LVDS cable and we now have a picture, but this shouldn't cause odd behavior with the KB & TP? But it might be the cause of reversed colors on the display but we cannot fully varify until we can get past the set up screen.
Disconnect the keyboard and plug in a USB keyboard does that work?
DanJ さんによる
@danj I can try that, but pre boot I can do a PRAM reset so I presume the KB must be working, and when set up loads the function keys are working but the colors are reversed. This must be related to the LVDS cable which I will replace again tomorrow with another.
livfe さんによる
@livfe - The keyboard has two modes, the first is working as it's hardwired, the second mode is via a decoder chip within the logic board. Using a USB keyboard uses the external keyboard decoder.
DanJ さんによる
@danj OK so if I try the external KB and all is OK, then what am I looking for? It was all working fine before we replaced the LCD connector.
livfe さんによる
@livfe - inspect the area as you could have dislodged something.
DanJ さんによる