Chosen Solution

Hi iFixit Community, This Mac is pushing quite a few years and age-related problems are unsurprising, but this one’s got me totally stumped. After five days of sleep, the trackpad stopped responding to touch input, and couldn’t be revived by any number of NVRAM/PRAM/SMC resets (which usually worked when the trackpad decided to go funky). Most recently, the keyboard has also started to become unresponsive after waking from sleep until the computer is rebooted. No water damage occurred. I have access to some spare parts due to trackpad cable shenanigans from days past: 2x iFixit trackpad (excluding cables),1x iFixit trackpad cable, and1x original Apple trackpad cable (known defective) For clarification, in my attempts below, I refer to the Apple trackpad and cable as “original”, the two iFixit trackpads as trackpads “A” and “B”, and the iFixit trackpad cables as “1” and “2”. The setup currently operating inside the MBP comprises iFixit trackpad cable “A” and the original Apple trackpad. I’ve tried the following things, to no avail: RebootNVRAM/PRAM resetSMC reset (NVRAM/PRAM/SMC were reset multiple times now and after almost every later step)Checked that trackpad is still recognized under System Information – still there, from previous experience if the trackpad isn’t detected it doesn’t show up in hereDeleted trackpad preferencesTried updating software to latest version – macOS Catalina 10.15.6Tried diskutil verifyVolume and diskutil repairVolumeTried booting into Recovery to isolate if issue is software or hardware related – seems to be hardware related since the issue persists in RecoveryRan Diagnostic Test to see if any issues with trackpad were reported – no issues were foundTried booting into external boot drive to isolate if issue is software or hardware related – issue persistsTried original trackpad with original cable – this is a known defective combo, which gave me trackpad issues last year with wild inputs; no inputs were detected this time aroundTried original trackpad with iFixit cable ATried original trackpad with iFixit cable BTried iFixit trackpad A with original cableTried iFixit trackpad A with iFixit cable ATried iFixit trackpad A with iFixit cable BTried iFixit trackpad B with original cableTried iFixit trackpad B with iFixit cable ATried iFixit trackpad B with iFixit cable BDebugged in Single User Mode and saw errors arising from AppleUSBMultitouch saying “[HID] [USBMT] [Error] ReportID is invalid in AppleUSBMultitouchDriver::_deviceGetReportWithLookup” – I doubt this is the issue, since it should be driven by AppleMultitouchDriver; but as the trackpad is classified as a USB device under System Preferences I wasn’t too sureBooted into Recovery and saw that the error message mentioned above did not appear, arousing suspicion it is software related – again, I’m not sure if this is the issue; even though the error message didn’t appear the issue persistedTried replacing AppleUSBMultitouch, AppleMultitouchDriver, AppleTopCase kernel extensions with fresh kernel extensions from macOS installer – didn’t work because codesign is differentTried macOS 10.15.6 reinstall – also didn’t work, but the error mentioned in (20) was no longer presentTried fresh macOS install on a brand new partition – no luck here eitherProcured replacement iFixit trackpad cable, and tested with original trackpad – this was done on the suspicion that all my cables may be defectiveTested replacement cable with trackpad A – didn’t workTested replacement cable with trackpad B – didn’t workReseated trackpad and keyboard cables fully – didn’t workRemoved logic board to inspect CY8C24794-24LTXI USB controller connections for corrosion – I live in an area near the ocean where corrosion of metallic parts is inevitable after a few years, so I figured that might’ve been an unfortunate cause. However upon close inspection with a microscope looking for signs of corrosion, dejointing, or shorts no glaring issues were found with the chip or its joints. The ZIF connectors were also in good shape. I’ve also taken it to an Apple Genius, but they ran their tests, found nothing wrong, and told me I’ve already done pretty much what they would’ve done, if not more. This leaves me quite stuck with truly no idea what’s going on with my trackpad and keyboard subsystem. For now, I’ve started using the ol’ wireless mouse (and sometimes keyboard), and that should tide me through for a while. I’d be grateful if anyone has any input, or suggestions on things that I can try to hopefully revive my trackpad! I really do hope it’s not an unrepairable issue, seeing as I’m trying to wait out another year or so before my university education begins to get a new MBP. Thanks for your time! Harry

You could possibly try to find a replacement pad and connect it and see if the new pad works, if that’s the case, then its possibly just an old pad that just went past its due date.