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Tesla Autopilot tricked by sun reflection on old construction line covered by fresh asphalt

TappetoImperiale | 2025-12-29 08:52 | 149 views

Comments (76)
Al-Sadder 2025-12-29 16:13

This happens very frequently. In the Netherlands you are sometimes allowed to drive on the shoulder of the highway near busy cities and you run into exact this situation. Autopilot (I don’t have FSD) freaks out every single time.

cwhiterun 2025-12-29 16:15

That would have tricked me too. It looks like a solid yellow line. Terrible road design.

AllCapNoBrake 2025-12-29 16:23

Agreed.

ipokesnails 2025-12-29 16:24

Despite how good FSD is most of the time, situations like this are concerning. The dashed line on the right was clearly visible, so what did FSD determine was happening here, a merge? But it didn't signal for a merge or a lane change. It makes me wonder what would have happened if there was a car in the lane beside you. Honestly, I think this is a situation where "phantom braking" would have made more sense than just changing lanes without signalling. Edit: it turns out this is Autopilot, but my point still stands.

Nicnl 2025-12-29 16:28

This is basic autopilot, not FSD. Since the last update, the dashcam recordings show what system is being used: - FSD has a blue text saying "self driving" at the bottom. ([Example here.](https://pbs.twimg.com/media/G7r8nsnWYAEw-Ff.jpg)) - Basic Autopilot turns the steering wheel icon blue (bottom right). Basic autopilot only does lane centering + adaptive cruise control. It will try to center the car between anything that looks like lanes, no matter what.   Now the answers to your question:   > _"so what did FSD determine was happening here, a merge?"_ Nothing was determined, because basic autopilot blindly follows the lines and that's it. > _"But it didn't signal for a merge or a lane change."_ Basic autopilot don't do that. > _"It makes me wonder what would have happened if there was a car in the lane beside you."_ Under complex situations, Autopilot freaks out and goes into "[take over immediately](https://www.notateslaapp.com/img/containers/article_images/fsd-beta/take-over-immediately-toi-red-steering-wheel.webp/258965334767281e0515149eca0693ed/take-over-immediately-toi-red-steering-wheel.jpg)".

ipokesnails 2025-12-29 16:35

Oops, my bad. I've definitely had phantom braking with lines on the road that were way less sketchy than this though, I'm surprised the car didn't just bake here.

_thwip_ 2025-12-29 16:48

It also has trouble with stoplights where glare is present.

Signatureshot2932 2025-12-29 16:54

I’d have done the same if I was driving. Look at those line designs, it clearly suggests lane is ending on left so the car moved to the right. It’s a bad road design.

Noctew 2025-12-29 17:01

It‘snot bad design, it‘s construction crews not giving a shit. It is not acceptable to have old lines still visible when new ones are drawn or when temporary lines are removed.

Underwater_Karma 2025-12-29 17:26

I don't think "tricked" is the right word. The lane is very badly marked, the car behaved entirely appropriately

ramanana01 2025-12-29 17:35

Autopilot stops at lights?

pummisher 2025-12-29 17:37

I just got tricked thinking the car did the right thing. 🥲

attanasio666 2025-12-29 17:37

No because you have 2 human eyes which have way more resolution than a camera. It 100% looks worse on a video than in real life.

lilcreep 2025-12-29 17:43

I’ve definitely been tricked by things like this before with my human eyes. It’s not uncommon for road crews to do a shitty job

revaric 2025-12-29 17:58

This would happen to any lane keep system using front cameras.

_thwip_ 2025-12-29 17:58

Mine ran a red light once because the sun glare made it look green. I'm guessing it's a rare case but just like the video, you still have to pay attention and take over if necessary.

Batucagan 2025-12-29 18:34

It is not that wrong tbh

10-mm-socket 2025-12-29 19:04

Thankfully the tesla autopilot looks at your blind spots and surroundings before darting over in the lane. My only issue is the full self drive always seems to target pot holes. I constantly have to cancel and manually avoid them. 5 lane choices and it picks the pothole lane each and every time

tillyspeed81 2025-12-29 19:05

This is common in Texas, but lines usually run into a divider or other obstacles….

veganparrot 2025-12-29 19:08

That is not appropriate! The car behaved understandably, given the way its technology works and the way the road looked, but a good driver should recognize: "ok, I don't sharply merge into the lane next to me, this is the lighting being strange."

veganparrot 2025-12-29 19:10

It is indeed a bad road design, but would you really do the same thing? Even if I did, as soon as I realized the mistake, I would regret being tricked.

arnthorsnaer 2025-12-29 19:14

I would have done that too, don’t understand tricked.. what was the right thing to do.

Xx_HARAMBE96_xX 2025-12-29 19:16

Yup, there's a bridge over the highway I go through every day being repaired, under it one lane was cut because of that for a good distance, so all the lanes have a similar yellow line redirecting all the lanes to the ones next to them, and they all look as shitty as the one in ops video

Xx_HARAMBE96_xX 2025-12-29 19:19

Wouldnt it actually affect all lane keep systems? Unless maybe there's one that blindly works by gps or by the side barriers

veneno11 2025-12-29 19:25

Can you retry the test with a car following close behind but in the other lane. Would it still try to merge infront of the other car or continue straight?

Split_Dodge 2025-12-29 19:29

Mine dodged a pothole today on the highway I was impressed

digitalgoodtime 2025-12-29 19:34

It's not a painted line but rather freshly laid asphalt which has a shine/sheen to it compared to the road. It was most likely used to fill a crack or something. Tesla thought it was a lane marker and this is why I don't buy or use FSD, even during the numerous free trial periods Tesla has offered.

Noodle36 2025-12-29 19:40

Autopilot doesn't stop for red lights, only FSD does.

su1cid3boi 2025-12-29 19:41

Its not a real painted line, its one of those tar snakes thar reflect the sun and look like yellow paint

Odd_Algae_9402 2025-12-29 19:43

Yep. This is when I decided I didn't care for autopilot. That and the potholes it aims for. Not worth $100/mo. And following others so close when I'm expected to intervene if it fails. It may drive better than most people, idk. I'm not most people, however.

_thwip_ 2025-12-29 19:56

That's what I meant, sorry

Organic_Battle_597 2025-12-29 20:08

Yeah this sort of edge case is exactly why real FSD will be a pipe dream for the foreseeable future.

Cimexus 2025-12-29 20:19

Consumer grade GPS is not accurate or reliable enough for something like lane keeping. It’s only accurate to within a few metres, which is more than the spacing between lanes.

TheEvilBlight 2025-12-29 20:53

This is why simply painting over lines isn’t great. The reflectance change causes it to stand out, though jackhammering the paint out and resurfacing would be pricy.

Ok_Priority458 2025-12-29 21:20

Sun has got nothing to do with it ,happens at night as well...using autopilot during construction zones is dangerous when there are multiple road lines visible. You need to be alert to intervene or just disable autopilot....thats also why fsd can never be FULL SELF driving because it will always need assistance under certain circumstances.

YeetYoot-69 2025-12-29 21:38

This honestly might've tricked me

HekkenFratz 2025-12-29 21:44

"Old"

[deleted] 2025-12-29 23:02

There was a road like this where I live and I did the same thing when I first saw it..

egoomega 2025-12-29 23:34

Alabama?

AllCapNoBrake 2025-12-29 23:38

My dad who was a PM for the DOT for 43 years was over road construction and you've never met a man more passionate over "MOT" (maintenance/movement of traffic). Poor MoT can and has absolutely caused carnage and even death for a bunch of reasons, some the fault of the driver(s), and others due to poor traffic controls (ie poorly removed lines from interstates).

Blooean 2025-12-29 23:52

Free lane change without EAP or FSD!

LakeSun 2025-12-30 01:58

Did they not just push an update to fix this?

Xx_HARAMBE96_xX 2025-12-30 03:43

Yeah thats what I wanted to mean with blindly, yup basically being as reliable as going blind

Pappa_karp 2025-12-30 04:01

Nope. Doesn't happen on my comma

tom_zeimet 2025-12-30 05:29

FSD beta is not available for consumers in Europe, OP is from Italy and this is just the normal auto steer.

AppropriatePlum1006 2025-12-30 07:06

If its an old line just remove that crap, seriously. This is for humans confusing let alone machine learning systems

hopefullydtf 2025-12-30 08:06

lol you people are such a cult

Desperate_Exercise13 2025-12-30 13:14

Yes that happens

revaric 2025-12-30 13:30

Not if it only used side cameras, like a lane assist feature, since the glare is a factor of sun angle.

revaric 2025-12-30 13:32

Comma isn’t a lane keep technology specifically. This would t happen with FSD, and probably wouldn’t happen with Waymos either.

kftnyc 2025-12-30 15:52

Once fleet reporting is in, pothole avoidance can be godlike. Every car choosing the smoothest line down every street based on the experience of every Tesla that has gone before. Until then, around town FSD is unusable where I live.

Xx_HARAMBE96_xX 2025-12-30 16:58

Well, how would a side cameras only lane assist behave if there was a zone without visible lines be it because of bad maintenance or any other reason? I can use autosteer in my urbanización without problem going at like 30kph even going over bumps and do any sharp turn, and there are no lines drawn, is the no visible lines a drawback for side cameras only?

Pappa_karp 2025-12-30 17:02

How would you describe the comma then?

Schnitzhole 2025-12-30 17:10

Damn got me too looking at the footage

Opening_Pizza_9428 2025-12-30 17:20

My consumer grade racebox device has a precision of about 0.2 meters usually.

Opening_Pizza_9428 2025-12-30 17:21

Or in rain.

Signatureshot2932 2025-12-30 21:40

I think car is making a choice between honoring solid line vs dotted line which it obviously chose the correct. It’d rather cross dotted line than solid. I would have immediately gone back to left lane after figuring out the inaccurate lines but I guess car decided to stay in right lane.

woodenpigeon1 2025-12-30 23:52

This needs more upvotes.

[deleted] 2025-12-31 00:05

So a legacy piece of software from 2016. Yeah this is a non-story.

hasbigdog 2025-12-31 00:13

What would you expect it to do?

bsears95 2025-12-31 00:32

This happens to me a lot on Colorado. Low sun angle or wet roads and these grooves look just like the other elane lines (sometimes ever more like them since our main line lines fade often). Once you learn them you can ignore them, and FSD won't "learn them" for future trips, so it wont ignore them, but the road really should be cleaned up better .

No_Complaint_765 2025-12-31 00:56

Autopilot can definitely afford to do better. I had similar situations where it makes similar mistakes, it takes turn lane markings from perpendicular road as its lane and ends up swerving to the wrong lane. In this particular case, it should technically recognize that the marking was invalid due to the surrounding lane markings.

OneIndependencee 2025-12-31 02:37

I'd do the same if I were a camera.

Primary-User 2025-12-31 03:13

I’d probably have changed lanes myself because you never know what’s coming after when there is a solid line like that.

revaric 2025-12-31 15:25

Most systems today only work with clearly visible lines.

revaric 2025-12-31 15:27

Last I was tracking it was attempting SAE level 3 driving assistance.

Acrobatic_Constant79 2025-12-31 21:30

I am having such issues every day. Place where I am has many roads with worn out drawings so not tesla but even my eyes quite often can not solve the puzzle In this shot... well...not that obvious at the very first point what you actually see

FlugMe 2026-01-01 03:43

Stereoscopic vision allows humans to determine what is a reflection (of sunlight in this case) vs. a solid albedo colour of a surface. Most humans, given this situation in real life, and determine a painted line vs. the black asphalt paint stuff. The car failed the perception test, like most monocular cars would.

Mister_Prometheus 2026-01-01 15:19

Poorly marked lane. I think the real test would have been how the car would react if there was another car to its right in the lane it went into.

SnickerdoodleFP 2026-01-01 18:32

Comma is level 2, not level 3.

SnickerdoodleFP 2026-01-01 18:33

Lmao despite the downvotes, my Comma also doesn't react this badly in the same scenario. Jacksonville is always under construction so this is pretty common

One-Government7447 2026-01-02 12:22

Cant wait until these systems are more common and a family dies in a crash for some redditor to say "the car behaved entirely appropriately"

brunoburz 2026-01-03 14:45

I love FSD and use it all the time… But no way is it worth $10,000. I am so glad I paid $2000 for it in some kind of flash sale years ago. It’s getting better. It will get there. But no way is it worth what it is today nor what Elon Musk is saying it is today.

Mister_Prometheus 2026-01-04 19:59

This is not the fault of the FSD system but rather the fault of the construction company failing to cover those lines up properly.

Hockeyshot39 2026-01-08 10:57

Lmao bro almost 300 downvotes

grogi81 2026-01-25 09:29

I would be fooled myself.

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