DIY UV Treatment for Yellowed MCU Screen

[ucmndd]

These may not be so dangerous, but I typically default to "be afraid" when I'm not sure about some things (see gasoline / springs)

It’s basically a hobby light - something you’d see in a haunted house or rave.

Probably don’t stare into it or anything, but I’d likely not classify as being as dangerous as gasoline vapor.

It’s a 50 watt lamp. For reference, sunlight emits about 32 watts of UV radiation per square meter at ground level.

 

[dark cloud]

A few years ago at the dentist he stuck a UV light in my mouth to cure the filling.

 

[Naekuh]

@cduzz i think you are thinking the uv lamps found in uv sterilizers.

The UV lights the poster uses are party lights, almost on the same league as a black light you find in houses to make things light up.

The only thing i would really worry about is photo bleaching something with the light, hence why he covered up as much as possible with a towel.

There is also the probability he could of nuked the LCD's but were assuming the curing glue would of absorbed most of the UV before it got to that.

 

[MichaelP90DL]

Wow! I don't get it..your cars build 2018 mine is 2017 and we have it but MichaelP90dl above is 2015 and states he does not have the issue?

I don't get it either, but Tessie's screen is perfect. So far.

 

[whitex]

That rig makes me super itchy; hard UV is *super* dangerous. Like "oh, hey, you're blind for life now haha!" dangerous. It is not to be trifled with.

Now, captain awesome is probably pretty safe(ish) running a cardboard and blindlight rig like that once every 3 years to mange his car, but a tool left floating around in a workshop of a billion dollar company has a significant safety threshold to achieve before you can safely deploy it, otherwise you get lots of "hey, now I'm blind" lawsuits. Similarly, there is no way *I* would sign off on writing this procedure down for the consumption of other organizations (3rd party garages / DIYers) -- way too much liability unless you're making a specific tool and a big pile of safety equipment.

Similarly, there was (hopefully) quite a bit of work done to characterize the after-effects of this work on the other functionality of the panel, test proper bake time, proper light / frequency, etc.

There are plenty of things you can do on a car that are "make a mistake and you're ruined for life" (gasoline vapors / steel suspension springs / lifting the car) -- hard UV is absolutely as dangerous as any of those if not treated with proper respect.

So bravo adventurous OP for achieving this, and congratulations on characterizing how it works. This is likely the first step in a proper aftermarket procedure for managing the yellow ring of sorrow.

But I wouldn't read too much into "hey why did it take tesla so long to make this tool" (the answer is: "worker safety / attorneys" ) (and "limited interest in actually dealing with worker safety / attorneys" )

They have machines deployed now, do you think they are not safe to use? So your theory is that the reason why they don't have one in each service center but ship it from SC to SC, and the fact that they don't replace worn-out or broken ones, is because they want to only expose a limited number of employees at a time to the risk of being blinded?

Btw, here is one simple technical solution: Make a "UV baking drawer" sized to fit the display. Procedure is to remove the display, stick it in the drawer, let it bake. The drawer has safety interlocks which will not turn on UV until closed and turn it off if drawer is opened. Add a timer for convenience. Done.

 

[whitex]

Wow! I don't get it..your cars build 2018 mine is 2017 and we have it but MichaelP90dl above is 2015 and states he does not have the issue?

2015 screens didn't have the yellowing problem - they had the bubbles in the screen and leaking goo problem instead. I have 2015 and 2018 cars at home, 2018 developed a yellow screen, 2015 (now out of warranty) screen still ok, though I know the bubbles are likely comming, so might seal the screen when I take it out to replace the emmc soon.

 

[whitex]

One of the things I learned researching this is that UV LEDs do in fact “wear out” rather rapidly and only emit in the necessary spectrum for a relatively short period of time (low hundreds of hours). Not a problem for most applications but you can see how quickly it’s possible to hit that threshold in a service center running the thing 10 hours a day.

Appreciate all the comments and feedback but I’d also request that the complaining about Tesla’s approach or lack thereof is reserved for one of the other 1500 pages of threads on that topic.

The solution to "wear out" is replaceable UV light-bulbs. Or is changing light bulbs a foreign concept to Tesla designers?

 

[ucmndd]

The solution to "wear out" is replaceable UV light-bulbs. Or is changing light bulbs a foreign concept to Tesla designers?

I suspect based on the images we’ve seen of the tool and the reported power requirements and time to service a screen, they’re using an array of rather powerful LEDs, which is undoubtedly more complex to replace/service than unscrewing a light bulb.

Certainly not impossible, but another reason why deploying a commercially viable solution needs time. At some point you need experience in the field to test longevity and performance before you manufacture base units and consumable parts at scale.

 

[TonyT]

Well I have a spare screen I plan to just shine the light on and cover up everything around it in my garage. Will see how it looks after... What's the worse that can happen?

 

[D.E.]

Well I have a spare screen I plan to just shine the light on and cover up everything around it in my garage. Will see how it looks after... What's the worse that can happen?

Why not try sunlight? There’s about as much UV on an overcast day as a clear day. I’ve used overcast daylight to cure optical cement for a telescope lens. If your screen is out of the car, it seems it might be easy to put it outside for a day. I’d love to know if sunlight will eliminate the yellow.

 

[Country Roads]

Had an hour in the car this morning to look things over in the light of day.

The horizontal line at the top of the screen, which was previously the most pronounced and easy to see, is completely gone. The vertical lines on either side are about 75% improved but still faintly visible. I think this is due to the way I had the light positioned - the center of the screen was getting most of the direct light. Going to do another session this evening and re-think the way I've got the light positioned to more directly address the right and left edges of the screen, one at a time.

In all, worth price paid. Very pleased.

I'm on pins and needles. Let us know how the second treatment goes. Tired of waiting for the service center to call me in to get it fixed (again; screen already replaced once).
Appreciate

 

[ucmndd]

I'm on pins and needles. Let us know how the second treatment goes. Tired of waiting for the service center to call me in to get it fixed (again; screen already replaced once).
Appreciate

It’s cold outside and my wife got home first and stole the garage, but I’ll give it another go in the next couple days. Will definitely post a follow up.

 

[FlatSix911]

My late 2016 Model S was one of the earlier cars to exhibit the infamous yellow ring on the 17” MCU screen. I had it replaced early on, right before my warranty expired, before the prevalence of the problem was really known. Now about a year and a half later, the replacement screen has once again yellowed and I’m well out of warranty, about to turn 100,000 miles. I’m far from a service center, have no idea if Tesla would charge me for the UV treatment, if they even have the tool, and frankly don’t have the time or interest to fight with their service organization about it.

But hey, it’s just UV light, right? How hard could this be? I did a little research and determined that most adhesives for glass bonding are cured with UV light in the 365-400nm range. After a little poking around on Amazon looking for a reasonably powerful light in that spectrum, I settled on this bad boy for $35:

https://www.amazon.com/dp/B07MDWKNMK

It arrived the next day and I set out to fashion a rig of sorts (read: stack of cardboard boxes) to position the light in front of the screen and see what happened. I took some basic precautions to cover the dash with towels - didn’t want to risk yellowing the lacquer on the wood dash parts or anything.

Long story short, it’s dark now so hard to know for certain but first impression is that after 4 hours of baking the yellowing is dramatically reduced, but not quite gone. I’m going to examine things in the daylight tomorrow and based on what I see do another 4-6 hours and reassess. As of now I’m quite pleased with the results for $35 and am reasonably certain it will get even better with a little more time.

Before:
View attachment 481061
View attachment 481062
View attachment 481063


Shots of my “rig”:

View attachment 481064
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View attachment 481066


After:

View attachment 481067


I know it’s kinda hard to see the results in the pics, but it looks markedly better in person. Will try and get some better shots tomorrow.

Well done!

 

[cduzz]

Not sure what you mean by "Hard" UV @cduzz but the lamps and wavelengths mentioned here are not as dangerous as an Easy Bake Oven, or a kids blacklight poster. It is the same thing as a nail polish curing light - which will also work in this case.

I believe you are referring to the much more dangerous UVB spectrum found in grow lights, tanning beds, lizard lights etc. which is indeed very dangerous, but then again so is sunlight.

A little more research on my part -- the lights that were used to erase eproms "back in the day" were "UV-C" lights under a hood that had a little mechanical safety switch to keep the bulb from coming on unless the hood is closed. Nasty nasty stuff.

If these lights necessary to cure the screens are lower energy / longer wave-length UV, so much the better.

 

[dannycamps]

I figured it was only a matter of time before someone came up with a DIY solution to this. Kudos to the OP. Now as to why Tesla is so slow in rolling this out, there are other costs involved. For this procedure to work, the car has to have the device attached to the screen for several hours uninterrupted This means the car being treated will tie up a service bay in an already crowded and overbooked service center (e.g. fewer cars can be serviced in a day, lost fees/labor).

You could argue that they can treat these cars overnight (or outside) but I wouldn't be so willing to leave a UV death ray machine that supposedly runs very hot unmonitored in an area surrounded by a bunch of cars with lithium battery packs that do not seem to like fire too much.

The other problem is that Tesla has to fabricate this UV tool. Elon can't just walk to the local Sears Auto Center, see that it's out of business because Sears is a near-dead brand, then head to AutoZone to buy this thing. I'm sure it's not cheap to produce and if they have a high-rate of failure, it only increases costs exponentially.

 

[TonyT]

Why not try sunlight? There’s about as much UV on an overcast day as a clear day. I’ve used overcast daylight to cure optical cement for a telescope lens. If your screen is out of the car, it seems it might be easy to put it outside for a day. I’d love to know if sunlight will eliminate the yellow.

I was thinking about that also. Guess our glass has a lot of UV protection, but I was wondering why it yellows and we use UV to get rid of the yellow.

 

[TonyT]

The 2015 pre-refresh screens have a different issue where they develop bubbles and leak goo from the bottom.

I've think I've seen a screen that bubbled and yellowed...

 

[MichaelP90DL]

I've think I've seen a screen that bubbled and yellowed...

You folks are giving me a lot to not look forward to. LOL

So far, for some unknown reason, no yellowing, no bubbling, no oozing goo. Nothing. However, "tomorrow is another day" (--Scarlett O'Hara).

 

[cduzz]

You folks are giving me a lot to not look forward to. LOL

So far, for some unknown reason, no yellowing, no bubbling, no oozing goo. Nothing. However, "tomorrow is another day" (--Scarlett O'Hara).

People rarely come to an internet discussion forum to report that nothing noteworthy happened to them today.

Today, I got in my car and drove it to work.

The battery (the worst 90 pack formulation) is still at the same capacity (or slightly better) than when I bought the car 6 months/5000 miles ago. 250 miles at 90%.

The screen worked; it's a little dusty and has a bunch of finger prints.

The door handles came out when I walked up to the car; I tugged on the handle and the door opened.

The extremely minor squeek from the side of the passenger seat against the center console continues to make a tiny amount of noise when my son moves around.

The AC worked without the fuse blowing and defrosted my windows.

I drove the car in reverse several times while I was turning the steering wheel and the suspension did not fall apart.

I listened to several podcasts using the built-in MCU1 and the 4 year old emmc did not wear out stranding me.

I plugged it into the free charger at work and the car is charging without the charging system failing.

Another day another hail of fail avoided!

 

[quickstrike12]

People rarely come to an internet discussion forum to report that nothing noteworthy happened to them today.

Today, I got in my car and drove it to work.

The battery (the worst 90 pack formulation) is still at the same capacity (or slightly better) than when I bought the car 6 months/5000 miles ago. 250 miles at 90%.

The screen worked; it's a little dusty and has a bunch of finger prints.

The door handles came out when I walked up to the car; I tugged on the handle and the door opened.

The extremely minor squeek from the side of the passenger seat against the center console continues to make a tiny amount of noise when my son moves around.

The AC worked without the fuse blowing and defrosted my windows.

I drove the car in reverse several times while I was turning the steering wheel and the suspension did not fall apart.

I listened to several podcasts using the built-in MCU1 and the 4 year old emmc did not wear out stranding me.

I plugged it into the free charger at work and the car is charging without the charging system failing.

Another day another hail of fail avoided!

I love my car(going on 2 years now) and it’s been the best decision I made outside of my family. but OMG had I found this forum PRIOR to my purchase I would have maybe never even got one.