MacBook Pro 16" M3 Max Screen Horizontal Line Issue. Denied Warranty Despite Known Design Flaw

SethNamin wrote:

I took it to two different Apple service centers, and they refused warranty coverage. They told me it could be caused by pressure or liquid damage. But here’s why this doesn’t make sense to me:

My keyboard once had a small liquid sign near the space bar, but the keyboard still works perfectly fine.

Even if the keyboard had liquid damage, how could that affect the middle of the display?

Liquid damage can be insidious and pervasive. By nature, liquids flow. A small spill near the space bar means liquid may have flowed into the chassis under the space bar then flowed somewhere else over the logic board before evaporating. Some time later, corrosion sets in where the liquid evaporated and damage begins. In other words, the display issue is likely not caused by liquid damage to the display itself but rather to a component on the logic board.

Apple includes liquid sensors inside the chassis and if any of them indicate liquid ingress, they will not cover the repair under the standard warranty (though the separately purchased AppleCare+ plan does cover liquid damage).

A perfect, razor-straight horizontal line across a MacBook screen is almost never user damage, that’s a panel or controller fault, not liquid. Liquid damage shows up as splotches, bleeding, or uneven marks, never a clean stripe.

SethNamin wrote:

My keyboard once had a small liquid sign near the space bar, but the keyboard still works perfectly fine.

Even if the keyboard had liquid damage, how could that affect the middle of the display?

So you aren't clearly saying whether there was water damage. But it sounds like there was: "My keyboard once had a small liquid sign near the space bar" So was there liquid damage or not? As neuroanatomist explained, once water gets into the laptop keyboard, it can travel and cause insidious internal damage that might show up sometime later. I have seen people spill liquid on a laptop keyboard and the laptop stops functioning, not just the keyboard.

If there was any liquid damage (was there?) at all at some point (I think you know if there was or was not, can you clearly and unambiguously respond to that question?), then the regular warranty does not cover that because the regular warranty is to cover manufacturing defects, not user caused damage. The AppleCare+ in some cases does cover water damage, it is like an insurance policy that can cover some user caused damages.

By the way, I don't see the horizontal line you mentioned in your photos.

Sorry, but unless Apple releases an Apple Service Program for this device, there is nothing you can do, if Apple decides, that this issue is not covered by the warranty.

Apple Service Programs - Apple Support