Why precisely does the trackpad cable fail?
I hope to find answers to some questions to help illuminate the root cause behind the well known issue regarding the trackpad cable for A1502 2015 Macbook Pro 13”. I also want to explore the difference between the cables sold by 3rd party sellers (which I allege are non-genuine) and the official Apple trackpad cable.
If you search the forums or the Internet for “A1502 trackpad cable” it is abundantly clear that there is an issue pervading Early 2015 Macbook Pro 13” where the keyboard & trackpad is finicky or ceases to work.
The solution is to replace the trackpad cable with Apple part number 821-00184: MacBook Pro 13" Retina (Early 2015) Trackpad Cable.
This was my experience. I bought the part from eBay ($13 AUD). As experienced by some of the reviewers in the above link I also encountered the following issues: (1) there was too much slack in the cable and it was unusually longer than the genuine apple cable that it replaces and (2) the keyboard & trackpad worked fine but there was no haptic feedback.
I really needed the haptic feedback so I bit the bullet and went direct to the Apple store in Sydney. I explained what I had done and they agreed that the trackpad cable is the issue and said that only genuine Apple parts could be purchased via the store (which is probably well known by iFixIt regulars). They replaced the cable and it worked fine. So I bit the bullet and paid for the $15 part and $120 (again AUD) for the few minutes of labour.
This has been racking my brain though. The original cable that failed in my laptop seemed perfectly fine. Here are links for it: http://ks.fastmail.com.au/2015mbp13-trac... . I honestly couldn’t see any wear or tear.
In contrast here is the ebay cable http://ks.fastmail.com.au/2015mbp13-trac....
The geuine replacement cable done by the Apple store did not have a orthogonal fold for the bottom slide-in connector. It appears there was some more slack.
Here are my questions:
Q: is this a software issue or a physical issue with the cable?
One of the reviewers said this about the trackpad cable: If your track pad and keyboard stop working in macos, but still work in other operating systems like Linux, this may fix the issue for you. I was thoroughly confused why my trackpad and keyboard worked when booted into Linux but not Mac os, but I eventually found someone who said to just replace this and it worked! Who knows why.
I had a similar experience. When the keyboard & trackpad became finicky, I noticed that on resuming the laptop from sleep the keyboard would work fine but the gestures or haptic feedback will stop working. Sometimes just a simple reboot of MacOS Mojave (10.14.5) would restore functionality. Only to stop working after the laptop is resumed from sleep again. This happened for awhile until one day both keyboard & mouse ceased to work and I got the insert keyboard & mouse screen: http://ks.fastmail.com.au/2015mbp13-trac....
I then opened the laptop and reseated the cable and everything worked fine again. For awhile, until it died completely and reseating was no longer an effective remedy. I had to resort to external keyboard & mouse until the replacement cable from ebay arrived.
Q: Why does the haptic feedback not work for some of the non-genuine of the cables? Does this affect some or all non-genuine cables?
So my eBay cable was almost fully functional, only haptic feedback didn’t work. This is what prompted me to get a replacement from the Apple store because i actually thought the issue was more than just the cable. Except Apple replaced the cable with a genuine one and everything works fine.
A review from the iFixIt part link above says this: I used this to fix a trackpad and keyboard that would periodically stop working. It seems to have solved the problem. Only thing is now The Haptic feedback on the trackpad is unresponsive. Has anyone had a similar issue? trackpad works like it should there is just no haptic feedback which is disappointing.
So it’s not just my eBay cable but also iFixIt cables. A different user reports the same issue (which I also responded to): Trackpad works but haptic feedback not there.
Q: Based on the previous questions, is the physical cable more than a ribbon cable? Does it have a special chip or some kind of proprietary system? Why is it hard to replicate a genuine cable?
Q: Will this be a never-ending recurring problem?
A reviewer says this: If your keyboard and trackpad stop working on this model, this flex cable is the likely culprit. My first one lasted 2 years, and was replaced under AppleCare. That second one lasted 2 years also. Now I just installed my third flex cable myself, purchased from ifixit. This one was a bit longer than my previous one, so I used a bit of an "S" fold to fit the redundant bit near the lower connector. So far so good!
This is asinine! So two genuine apple cables and a iFixIt one which sounds similar to my ebay cable with regards to the elongated cable with more slack. This reviewer seems to indicate that there were no issues with haptic feedback.
Q: Does Apple acknowledge this as a well known issue of the 2015 Macbook Pro 13”?
It took Apple a very long time to acknowledge the butterfly keyboards were defective by design. Similar with flex gate with the display connectors. It was abundantly clear when I took it to the Apple store for service the repair tech knew the trackpad cable was the culprit (maybe after explaining to her that I replaced it).
Q: Is this a defective design?
This is a well known issue that spontaneously happens to several A1502 Macbook Pro 13” laptops. Is this a design defect or a wear and tear? I did a cursory investigation of 2013-2014 Macbook Pro 13” which are A1502 as well but they didn’t have this issue. It seems that the keyboard and trackpad use separate cables. Also the trackpad cable is underneath the battery (that is, the cable cannot be seen after removing the bottom shell of the mac). I think in 2015 model they piggybacked the keyboard on the trackpad cable and so they must have a new logic board chip that integrates a controller for both. It certainly is much easier to replace the trackpad cable (it took me about 20 minutes total to disassemble, swap trackpad cable, test everything, and reassemble). So that is a plus. But the spontaneous and apparently recurring breakage of the cable is very suspect and I don’t know if this is considered a defect.
I’m really sorry about the length of this post and all the questions. But I also hope that someone experiencing the same issue can find a lot of the surrounding issues with the trackpad cable centralised here. Thank you.