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Trash blowing across freeway put my car into emergency braking

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GasKilla

No Gas Know Peace
Nov 11, 2015
659
273
Los Angeles, CA
I was in moderate traffic (car in front of me was several car lengths ahead of me, not locked on in blue) with TACC and AP engaged when my car started braking and flashed the red collision car graphic. I was very confused because the car in front of me wasn't braking and was quite far away, then I noticed a disgarded bag of chips (the kind with the metallic looking liner) floating across the lane in front of my car. As soon as my car cleared the bag everything went back to normal. I have yet to receive the 8.0 upgrade so I'm still on 7.1, I'm wondering if the reprogrammed radar would behave in the same way with 8.0.
 
I was in moderate traffic (car in front of me was several car lengths ahead of me, not locked on in blue) with TACC and AP engaged
TACC and AP were "engaged" but you were not "locked on" to the car directly in front of you?

Sorry, I'm confused by what you are describing. In any case, it is interesting that the 7.1 AP decided that small bag was a serious obstacle. Such a situation is certainly a challenge for AP and demonstrates why the driver always needs to pay attention.
 
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car in front of me was several car lengths ahead of me, not locked on in blue
The car was probably too far in front to be locked on; therefore, AP will look at the lanes instead.
I suppose it all depends on what the OP meant by "several". I am interested to hear from him as to approximately how far in feet the car in front was from his car. And I don't understand what "TACC and AP engaged" means if they were not "locked in blue". Maybe by "engaged" he means the icons were shown in grey, so those two functions were available to use but were not in use because they weren't shown in blue?
 
I was in moderate traffic (car in front of me was several car lengths ahead of me, not locked on in blue) with TACC and AP engaged when my car started braking and flashed the red collision car graphic
Yikes, but it triggered just the alert, right ? Your thread topic suggested to me that EB was actually activated.

My mind is still trying to deal with what will happen in a future 8.x release where radar can trigger the brakes in this case...
 
(car in front of me was several car lengths ahead of me, not locked on in blue)

Yeah, I'm confused by this, too. I've never seen the car I'm following highlighted in blue.

That being said, I have experienced emergency braking twice while in AP mode, where the car in front was highlighted in red. Fortunately there were no cars behind me otherwise I surely would have been rear-ended. Never saw anything on the roadway that would have triggered the event.
 
Yeah, I'm confused by this, too. I've never seen the car I'm following highlighted in blue.

If you've never seen the car you're following highlighted in blue, the lane markings where you live must be incredibly good and you must have never used AP in stop and go traffic.

For me, living where the lane markings are incredibly bad, AP often switches from following the lane to following the car in front of me. That, plus a lot of stop and go traffic where AP has no view of the lane means I see the blue car often.
 
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If you've never seen the car you're following highlighted in blue, the lane markings where you live must be incredibly good and you must have never used AP in stop and go traffic.

For me, living where the lane markings are incredibly bad, AP often switches from following the lane to following the car in front of me. That, plus a lot of stop and go traffic where AP has no view of the lane means I see the blue car often.

More likely it was in blue and I just never noticed it. This summer I travelled thru downtown SanFrancisco, Vancouver, Seattle, Chicago, DC, Jacksonville, Atlanta, and Austin entirely using TACC and I doubt all of their lane markings are brilliant. :)
 
I suppose it all depends on what the OP meant by "several". I am interested to hear from him as to approximately how far in feet the car in front was from his car. And I don't understand what "TACC and AP engaged" means if they were not "locked in blue". Maybe by "engaged" he means the icons were shown in grey, so those two functions were available to use but were not in use because they weren't shown in blue?
I have my car length set to 5, so I'll guess the car was 5 or more lengths in front of me. By engaged I mean "on" or "activated" (steering wheel and mph highlighted in blue). I only get the car in front of me to "lock on in blue" in heavy bumper to bumper traffic, this was not the case in this situation.
 
I was in moderate traffic (car in front of me was several car lengths ahead of me, not locked on in blue) with TACC and AP engaged when my car started braking and flashed the red collision car graphic. I was very confused because the car in front of me wasn't braking and was quite far away, then I noticed a disgarded bag of chips (the kind with the metallic looking liner) floating across the lane in front of my car. As soon as my car cleared the bag everything went back to normal. I have yet to receive the 8.0 upgrade so I'm still on 7.1, I'm wondering if the reprogrammed radar would behave in the same way with 8.0.
Good to know this. The upgrade was mainly for door functions. We got 8.0 early Saturday morning. Can't comment if I like the upgrade yet. Maybe tap the brake to disengage AP then reengage after bag floats by. Like in NASCAR it could get stuck on the grill. Then AP might keep braking. Good to know non the less.
 
What message? I heard tones and saw the red car collision animation while the car was braking.
That's not AEB then. I forget the exact wording but on the IC a message stating "Emergency Braking in Progress" or something will appear.

Also, I had some thing similar happen today. Doing 75 on the highway, no cars around, the ghost red car appears and FCW appears and starts beeping and the car slows to maybe 65mph and then all is normal. It wasn't AEB though, just AP braking.
 
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It definitely seems like since the Joshua Brown incident, recent 7.1 updates do tend to err on the side of slowing down and moderate braking. In my experience it usually just lets go of the throttle or applies 50kW of regen braking. It feels like a lot, but it's definitely not "emergency" braking.

I've had AEB trigger in previous vehicles, and it easily knocks the wind out of you when the car suddenly slams on actual brakes.

Overall I think it's a good move on Tesla's part. The sudden slowing of the car is not enough IMO to cause rear-end chain collisions, but definitely gets your attention back on the road. Just quickly decide whether to press the brake or gas given what you see.
 
That's not AEB then. I forget the exact wording but on the IC a message stating "Emergency Braking in Progress" or something will appear.

Also, I had some thing similar happen today. Doing 75 on the highway, no cars around, the ghost red car appears and FCW appears and starts beeping and the car slows to maybe 65mph and then all is normal. It wasn't AEB though, just AP braking.
It all happened very quickly but I don't recall seeing a message. Either way it's all very interesting how the radar responded to the debris
 
TACC and AP were "engaged" but you were not "locked on" to the car directly in front of you?

Sorry, I'm confused by what you are describing. In any case, it is interesting that the 7.1 AP decided that small bag was a serious obstacle. Such a situation is certainly a challenge for AP and demonstrates why the driver always needs to pay attention.

If you have AP on and there are clear lane markings the car in front does not turn blue. It only turns blue if the car is tracking it and it only tracks the car in front if it cannot determine lane markings.
 
Please report all of your incidents to Tesla and any other appropriate authorities. There is obviously an issue with the AEB system. Hopefully v8 will fix it.
Way ahead of you ... I called the tech support people the day it happened, they said they'd pull the logs. I asked for a call back regarding what they find, and of course they said 8.0 (which I don't have yet) will solve some of these issues