820-3435 11" Air 2013 no keys no trackpad

This one had endured a tropical rainforest, which fried the display, but was still working on external monitor. I think, if I remember correctly, even keyboard and trackpad worked then on external monitor. So I installed a new LCD, and it boots up fine, except now the keys and trackpad do not respond. All else is fine. Maybe just the cables? Also need to mention that C2837 was corroded and came off. It is part of DP_TBTSNK_ML, Thunderbolt circuit, if I understand correctly. Would that influence the trackpad and keys? The cable looks clean and so do all the contact points on the trackpad and the board...
 
Thank you John. I will give that a try. Louis has a video where he says that if the MBA keyboard registers before boot chime, ( such as holding options) but not after, that I am basically screwed. He had many of these machines and never resolved it , I guess on a logic board level... So i can hope it is a component like the cable...This machine here also intermittently does not register the mag2 adapter...light on sometimes, but no always
 

2informaticos

Administrator
Staff member
The Magsafe light issue points to corrosion.
You must check the board and clean it better.
Also try known good LIO board/flex.

Test trackpad/keyboard disconnecting LIO.
See if you can access boot menu.
 
Thank you 2 info, I found a spec of debris in the L/O cable.Removing it it now keeps the mag light on. When I then disconnected L/O cable, and started it booted to desktop. Still no keyboard though...and fans running high. I cleaned the ends of the TP/KB cables and terminals, no cigar...
 
The keys do not work even before the chime anymore, as they did before once when I booted into Safe mode and brought up the boot menu via option. So no KB norTP either way. That is with L/O connected.
 
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And then again, it just now decided to boot for me via command R into recovery via bluetooth keyboard and USB mouse...So some keys must work before chime...
 

2informaticos

Administrator
Staff member
In OSX T/KB work under SPI mode.
Before logged in, USB mode is enabled.
If file vault is enabled, on password screen USB mode is still available.
Not working TP/KB anymore should be bad TP connector/flex/board, or missing some voltage to connector...
 
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