MacBook M2 trackpad diagnostic test error: Full surface cannot be sensed

First, check your battery for swelling. Symptoms:

— Unexpected trackpad and/or keyboard behavior.

— The gap between the display and the deck is not even when the display is closed.

— The gap between the bottom plate and chassis is uneven in places.

— Some of the screws that hold the bottom plate have popped out.

— The trackpad surface is higher than the surrounding deck surface.

— The computer "rocks" a bit on a known flat surface†.

† I find solid-surface and granite countertops very effective flat test surfaces.

If one or more of those symptoms exists, get Apple to evaluate as soon as possible. Sweling can get worse overnight, exerting enough force to irreparably damage internal components or enve the metal chassis of upper deck.

If there are no symptoms of a failing battery, then try an SMC reset. Please see:

Reset the SMC of your Mac - Apple Support

being careful to use the instruction set under the heading "Mac with Apple Silicon."

Beyond that, you'll need professional evaluation.

nishan131 wrote:

yes apple diagnostic. it seems when I hit to the track pad I am able to recover most of the parts in the trackpad as attached. I unplugged the trackpad from the jumper slot, clean it and re connected.

can it be a lose connection or a tight impact cause the issue?

https://discussions.apple.com/content/attachment/5355c768-9941-46bb-b94d-2a39ba1a3ea8

[Edited by Moderator]

Doubtful, looks like the Trackpad itself is not reading certain rows/areas.

I am assuming the bright green representing your fingers does not do that over that gray banded area which indicates a hardware issue at that area of the Trackpad. Now if the bright green does light up the gray area, but does not turn the gray blocks to the darker green, then that could be a diagnostic issue (I've never seen it, but I may never have used the service diagnostic for that particular model recently).

Edit: If you replaced the Trackpad or just transferred it to another Top Case Assembly, then you need to make sure you installed all of the Trackpad spacers (they can pop off with just the most minor movement as you install the screws). You also need to make sure the Trackpad is properly centered within the opening using the white plastic alignment guides provided by Apple with a replacement Top Case Assembly or Trackpad. Apple has guidelines for torque measurements for those Trackpad screws as well.

And did you run the System Configuration utility after installing the replacement parts from Apple? That may affect how things work & interact.

FYI, I just found out that after upgrading to macOS 26.x Tahoe there are multiple diagnostic tests available now when running the consumer level Apple Diagnostics. Instead of one diagnostic, there are now several tests to choose, such as MRI, Keyboard, and Trackpad tests.

If you are performing your own repair under the official Apple Self Repair Program, then this Trackpad issue needs to be addressed. If the Trackpad is functional, then you will need to contact Apple to see if this is a known issue with the Trackpad Diagnostic for that laptop, or whether it is a confirmed hardware issue with the Trackpad (especially if you have replaced the Trackpad) for the official self repair.

However, if you are not repairing the laptop under the official Apple Self Repair Program and your Trackpad is functioning correctly when used with macOS, then ignore the Trackpad Diagnostic since there is no sense spending money if the trackpad is working & only failing with the diagnostic test. Wait until the Trackpad is not working before having it repaired.

We are definitely missing out on critical details about why the OP is running the Trackpad Diagnostic.

Are you performing an official Apple Self Repair with your laptop? If so, it seems like your Trackpad may be bad. AFAIK, that is the only way to get such a Trackpad diagnostic.

If it is some third party app you found online, then contact the developer of that app.

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