Keyboard backlighting not working
Symptoms - White Keyboard backlighting doesn't work. Occurred after liquid entered left side of device when closed (side with MagSafe port). All ports work, key strokes work, CAPS LOCK LED WORKS, everything works other than white backlight.
Troubleshooting steps - I've basically done everything software wise, so I know it's hardware. Chat GPT seems to believe it's the backlight fuse that may have blown due to liquid entering.
Anyone have a hunch on what's happening? I know liquid is difficult, as I've actually worked at an Apple Store as a technician. This was a used purchase and I'd rather not spend a whole lot fixing it, but I'd like the backlight to work.
I do not have soldering equipment or a microscope, but I'm comfortable disassembling and stuff at home (I've replaced thousands of phone batteries and displays, and I build computers as a hobby). Thanks!
Is this a good question?
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The backlight for the keyboard that lights up the keys or the backlight of the display?
by livfe
@livfe The keyboard backlighting. Sorry, I thought I specified in the post. Thank you!
by Gabriel Conner
@gabrielconner That is what I thought, @danj Dans answer confused it ;)
by livfe
@gabrielconner have you checked the ambient light sensor and software settings? Cover the webcam area with your thumb to trick the ambient light sensor into thinking it is dark, and manually increase the keyboard brightness in the macOS Control Center to make sure it isn't related to a software override.
If your keyboard still won't light up, you need to open up your MBP and check the keyboard backlight flex cable and the logic board connector. Check the keyboard backlight connector for any signs of liquid damage, green corrosion, or burned pins. If the connector looks good use a multimeter and check the main power rail feeding the keyboard backlight driver IC.
Post some well focused images of the keyboard backlight connector and the surrounding logic board components with your question so we can see what you see. Use this guide Adding images to an existing question to add those to your question.
This is not to be confused with an answer. It is merely a request for more information to help finding a solution. IT IS A COMMENT!
by oldturkey03