iPad Pro screen unresponsive

This is a good summary of the problem. The Apple Store replace my first iPad Pro without asking questions. They check my second one and found the light leak. I don't know what will happen with this third one, but I won't go in until the problem becomes every few seconds continuously.

Feels like hardware to me, too. Something is coming loose, letting go after so much use. I keep mine in a rigid case, but also tested all three with no case and even sitting in the original packaging. Nothing makes a difference re: the behavior.

Thanks for your post.

To be even more technical: Apple uses a lot of flex PCBs.

They are known to need handling with care.

I have had invisible, hair-thin cracks in the copper on those PCBs.

The functional consequence is hard to predict, but surely messy.

I have had crosstalk into an undocumented test pin (cost us 6 months to find), I have had an erratic crystal oscillator in a correctly designed schematic (took us a year to find), I have had a chemically aggressive heatsink-glue setting a board on fire (too complicated to explain here; proud that we figured that out from the ashes).

What I want to say: The first thing you want as a test engineer in such a situation is an error report that is as precise as possible.

That’s what I am aiming at.

Working assumption:

The driver for the chip could be not from Apple, but from Broadcom.

Concurrency issues like to hide in low-level drivers, in my experience.

Maybe initially it was not designed for this situation, then got hacked.

People who are able to write good low-level drivers are a very rare species.

Corner cases can be triggered unpredictably by usage patterns or timing (i.e. temperature).

At least now I really know where I would like to take a closer look.

Given that there were so many dead ends apparently, we at least have a new _working_ assumption that largely fits the picture.

It’s an educated guess, but there are many things we do not know

I did not yet check, which iPads have two touchscreen controllers.

Maybe there is a historic relationship with increased resolution for pencil usage.

As before I am using past experience and concurrency issues in low-level drivers do look like that.

I do know of a case with a similar pattern where the root cause in the end was a faulty locking logic in a memory controller ASIC. We are not yet at the bottom of this, but it points at a location where maybe no one looked yet.

This is the kind of problem that does remain unsolved for a long time, because it does not hurt enough and it is confusing.

My hypothesis now is that it is SW, but outside IOS, that may nevertheless be correlated with IOS12.

And, yes, I may be wrong, so what?

Troubleshooting is like hunting. You decide what to hunt and then introduce fences.

I’d really like to know if someone already hunted in that corner.

Well, they are editing and deleting my posts, so maybe someone is listening...

And they ought to be interested, because if I am right then the issue will pop up again and again.

And basically I do believe that they are committed to quality and good user experience.

Anyway, at least it makes me and you feel better, doesn’t it?

It’s complicated. What if indeed the driver is from Broadcom, which itself outsourced it from a small programmer hut, where the programmmer used a template and has long since left? Imagine all the fingerpointing and denial!

That’s the way things tend to be and you do not want to be the manager of it (Trust me, I was!)

With all that it’s probably necessary to get the attention of an engineering manager, not the poor support guy.

Still: All of this is guesswork, but not worse than the guesswork we have read so far.

If I only had statistically reliable material about the distribution of this specific issue!

On the other hand: My goal is only to solve my problem ...

Dual touchscreen controllers are used by multiple iPads (not only pro) such as iPad 2018, iPad Air 3, ...

In older devices a different chip was used.

It seems to be correlated with pencil support.

The iPad mini 5 apparently has only one of the Broadcom chips.

That looks like a testable hypothesis: Ever seen this touchscreen issue on an iPad mini 5?

Yes.

As I have stated over and over and over...

This unresponsive touch screen issue, so far, in 9-months has ONLY affected the three model years of iPad Pros, with the exception of the 2016, 9.7 inch screen iPad Pro models and any of the newest 2018/2019 iPad models.

Rbylawski - please be assured that my earlier comments were in no way intended to reflect upon your valued contributions or actions in any way at all. Your posts are often amongst the more objective and balanced of those appearing here - and, to my knowledge, you have never descended into the belittling lectures of assumed knowledgable authority that are sometimes see here.

Indeed, your encouraging observation as to having two of the latest-gen iPad Pro 11” devices, heavily used, apparently working as they should that do not suffer touch screen issues, is actually encouraging - as it might suggest that not all iPad Pro touch screens are necessarily fundamentally broken. I presume that both we procured at a similar point in time from the same source, thereby, possibly, being from the same production lot.

By contrast, I have two Pro 10.5” devices in front of me now - otherwise identical other than one is currently running iOS 11.4.1 and the other iOS 12.3.1 - but both suffer from sporadically freezing touch-screen input. So, for the 10.5 at least, this issue is not confined to one major version of iOS.

Speaking still of my own specific observations relating to the 10.5s, the defect only became noticable after many months from new - which might suggest a latent fault brought about by component ageing/deterioration or mechanical failure due to thermal cycling. However, unless defective devices are forensically dismantled and examined with a microscope, this hypothesis is merely conjecture. Miniaturisation, such as that found within modern smart phones and tablet computers, introduces many challenges for physical layout and thermal management of increasingly tiny electronics.

Hopefully, continued constructive input here, from contributors with access to troublesome devices, might eventually prove fruitfull in shining a spotlight on this problem. However, waking the sleeping giant (Apple) is going to require unavoidably conclusive and consistent evidence.

Scratching together all my Austrian charme I compiled the following text.

Any comments before I fire it off?

Dear all,

there are reports that a few unlucky Apple customers experience touchscreen issues with their beloved iPad pros. And those reports are true, because I am one of them.

After a lengthy discussion in the Support community we would like to suggest to carry out a simple investigation.

Concluding from the facts that

- the issue tends to affect halve the screen

- there are two touchscreen controller chips

- the issue appears and reappears unpredictably

we suspect that there could be an undetected concurrency issue near the low-level SW accessing those chips which is triggered by some unknown timing corner-case.

We think this interpretation would fit the error picture and could explain quite a lot of puzzling observations such as the negative correlation with pencil usage.

Given that the issue can be severely annoying when it occurs and that service personnel struggles to assist customers when it does not it would be helpful to know if this non-trivial possibility has been looked at.

With sincere appreciation

maybe the both used daily a lot explains it. that's why i earlier mentioned the example about the headphone bug with ipad pro 2017. it only happened if you unplugged the headphones while the ipad was locked getting audio stuck in headphone mode. what if the pencil went out of contact with the ipad under unexpected conditions programmatically so the situation would only affect people with that setup. i can tell you for example i go through every screen in the settings app both for ipad and apps and configure every relevant option. most people wouldn't. so it's not what people software testing call the "happy case" or the most tested scenario. i find bugs all the time, but none as annoying as this one.

yes i have both pencils.

pencil 2 has a flat side, is all white, has no metal ring on top and can only be used with 2018 models. it feels more like a pencil. it docks to the top magnetically.

pencil 1 is round all around has a metal ring on top and can't be used with 2018 model. it docks to ipad through the lightning port.

the positive experience on my part was when pencil 2 was unpaired from ipad pro 2018 12.9"

As I said: Pooling brains helps in such a situation usually. I also hadn’t made the connection with charging.

Will test it ASAP.

Of course, when plugged in the device has less reason to throttle.

Let’s proceed with hypothesis H7: There is an issue related to charging.

It may be thermal, but might also have other relationships such as EMC i.e. increased electromagnetic interference between signals.

To understand the differences between models it would be necessary to know the precise layout of components.

Also power management ICs (aka PMICs) create heat and may influence neighboring ICs.

Again it would be helpful to get more empirical data.

This now is only a single observation, not yet statistically significant, as they say.

Do others also observe a correlation with charging?

I’m having the same problem with my iPad Pro 2nd Gen. I’ve even reported it to apple developers but they haven’t released any updates containing a fix or anything. I’ve read through some of the replies in the thread and I’m now going to try turning on my touch accommodations in accessibility in settings. Hopefully it could resolve the issue.

There really appears to be no rhyme or reason to this issue.

It does not affect every single iPad Pro made and this is happening to only a small crossection of iPad Pro models across all three iPad Pro model years.

Every iPad user uses their iPads differently, uses different apps, different accessories, etc..

All I know is that, currently, I am still running iOS 10.3.3 on my 1st gen, 12.9 inch screen iPad Pro and it is NOT experiencing any of these intermittent, unresponsive touch screen issues, really leading me to strongly believe that this is a software issue and not, necessarily, any hardware issue.

@MichelPM

There has been some back and forth regarding the estimated number of users who have this problem. One way to estimate is to count the number of apparently-distinct people who have spoken publicly about the problem. Another way is to assume that if "many" people report the problem, then most people must have it.

My background is in software-related human factors engineering. I have been a software designer, a development manager and a development director -- with a few other roles, ending as a software engineering professor. While I have not personally worked in software tech support, I have worked closely with tech support groups who provided assistance to customers of the software that I managed. My user bases were not close to Apple's, but they sometimes included millions of customers. I am retired now, but I usually worked with companies that treated support as a cost center rather than a profit center. That is, even if they charged for support, they charged less than they spent. Higher demand for support directly impacted our profitability. Structuring costs this way created a direct incentive to improve quality. They also created an incentive for managers, like me, to read up on support literature (academic and professional books, conferences, etc.) and to apply some lessons from that to the design or maintenance of our products.

I agree with MichelPM that probably not every iPad 12.9" user experiences this problem. However, 1000 reports probably represents a much larger number of people who have the problem. Studies of American consumer behaviour regularly find that many people do not report problems, that they are even less likely to report intermittent problems, and they are likely to stop reporting the problem if they are rebuffed the first one or two times (especially if they are rebuffed in a way that makes them feel as though they are welcome to call back or return to the store, but only if they bring additional information that they don't know how to obtain).

I tested this at one company, where I was managing a maintenance upgrade for one of our primary products. As with all software, our product had hundreds of open problems. The marketing department believed that only a few of these had a significant customer impact (and so we could address those quickly and start work on the product's next generation). Tech support believed that the product had an overall reputation for bugginess, that many people were being impacted by many bugs, and that a much broader upgrade was needed. Our call statistics supported the marketing view--when people *called us*, they usually mentioned the same problems. But we decided to do some outbound tech support instead of trusting the statistics. We filtered our product registration database so that we would call ONLY people who had never called us for support for this product. We called a random sample of a few hundred people, asking them how they liked the product and what problems they had experienced with it. We thought we were going to reach a few hundred well-satisfied customers who had few problems--instead we discovered that almost everyone had frustrating experiences that they didn't call us about because they didn't expect us to do much for them. Some gave up using the product. Many continued to use it but grumbled. The results were so impressive that we completely reworked our development plans and spent nearly a year rolling out incremental improvement to the product. We drove down support costs, nearly doubled our market share, and were bought out by our largest competitor (who had dominated the market for our type of product) when our share of new sales caught and then exceeded the competitor's. It became obvious to us over time that the volume of support calls was only the top layer of an iceberg worth of customer problems. That experience was career-changing for many of us who worked on that project.

I have no way to estimate the breadth of this problem, but it would not be shocking to learn that the 1000 reports visible to MichelPM might represent 50,000 or 100,000 affected ipads.

Don’t you think if the affected amount of iPad Pro models affected were this large, either Apple or the tech media would notice?

Users who own expensive Apple products are usually pretty vocal about issues when their Apple computers and devices do not work as they should or predicted/expected.

Just search for Macbook/Macbook Pro butterfly keyswitch issues and you'll see how vocal Apple users are about Apple products that have major mechanical or operational issues.

And I am here everyday.

It is not just me, either, that see this issue unresponsive touchscreen issue in these official Apple support communities.

Clearly, this does not appear to be a very widespread issue.

Apple product users are usually very vocal when their devices do not work as they should.