Model 3 increasing speed to 85MPH on its own

[devonian]

My model 3 sometimes increases the set speed to 85MPH when on autopilot. I have the settings set to current speed. Is I assume the car is adjusting the speed according to detected speed limit on the road, is there a way to overide this and keep the set speed at what I set it as? I prefer to choose the speed I want and not have the car continuously adjust he speed as it sees fit

 

[GRiLLA]

AFAIK if it's set to current speed it won't adjust with limits, if it was set to use the limit it would never increase speed above the initial speed at which it's activated. Are you sure you aren't catching the thumbwheel or using the wrong one when changing volume?

 

[Dranoel]

My model 3 sometimes increases the set speed to 85MPH when on autopilot. I have the settings set to current speed. Is I assume the car is adjusting the speed according to detected speed limit on the road, is there a way to overide this and keep the set speed at what I set it as? I prefer to choose the speed I want and not have the car continuously adjust he speed as it sees fit

I had the same experience yesterday. Set to "Current Speed" the car accelerated to the posted limit as we passed the speed limit sign. Never happened before. Currently on 2022.40.4.1

 

[MrBadger]

I had the same experience yesterday. Set to "Current Speed" the car accelerated to the posted limit as we passed the speed limit sign. Never happened before. Currently on 2022.40.4.1

Posted limits or 15mph (or more) over the speed limit?

Big difference. Car should never accelerate to exceed the local speed limit let alone the maximum speed limit possible which is what OP is posting.

 

[MrT3]

Posted limits or 15mph (or more) over the speed limit?

Big difference

Even accelerating to the posted limit is a problem if it is configured to ‘current speed’. Seems like the two issues might be related to the same bug. The OP‘s car may have thought the speed limit was 85 mph.

 

[devonian]

AFAIK if it's set to current speed it won't adjust with limits, if it was set to use the limit it would never increase speed above the initial speed at which it's activated. Are you sure you aren't catching the thumbwheel or using the wrong one when changing volume?

no definitely not catching the scroll wheel, The car also reduces the set speed when in a slower road area, is this normal when set to current speed?

 

[GRiLLA]

no definitely not catching the scroll wheel, The car also reduces the set speed when in a slower road area, is this normal when set to current speed?

I don't recall, I have it set to speed limit without an offset and only use it on motorways.

 

[Dranoel]

It was the posted speed limit. Trying to reproduce the same issue but, so far unsuccessful.

 

[BMW740iL]

this is an issue that is reported in more topics on this forum since V11 if I recall correctly. My car starts accelerating on highway junctions where the car overrides the set speed to the new speed limit that is allowed after the junction. Is this also where you experience this very disturbing behavior?

 

[UkNorthampton]

After one update, I had to set it to reading roadsigns and then back to current speed in order to reset.

 

[devonian]

this is an issue that is reported in more topics on this forum since V11 if I recall correctly. My car starts accelerating on highway junctions where the car overrides the set speed to the new speed limit that is allowed after the junction. Is this also where you experience this very disturbing behavior?

No it wasnt under these specific circumstances, in fact it happened twice at the same section of road, I will pay more attention when next on the same road to see if it happens again at the same spot

 

[yessuz]

My model 3 sometimes increases the set speed to 85MPH when on autopilot. I have the settings set to current speed. Is I assume the car is adjusting the speed according to detected speed limit on the road, is there a way to overide this and keep the set speed at what I set it as? I prefer to choose the speed I want and not have the car continuously adjust he speed as it sees fit

I noticed that with 2022.40.xx car does not recognise the speed limit (i.e. 70 on motorway).

Maybe that's the case?

 

[yessuz]

No it wasnt under these specific circumstances, in fact it happened twice at the same section of road, I will pay more attention when next on the same road to see if it happens again at the same spot

Check if car see the speed limit in the particular stretch of the road (indicates speed limit on the screen)

 

[15Peter20]

Doesn’t explain the OP’s issue, but I believe AP differentiates between single and dual carriageways, allowing higher set speeds on DCs but ‘posted limit + x%’ on SCs.

Mine occasionally takes a while to decide that what it thinks is a DC is actually a single, so will set a higher speed until it sorts itself out.

If the road then does turn into a DC but the posted limit doesn’t change, the set speed will increase to my allowed maximum configured in settings.

 

[devonian]

Resurrecting this thread as today I travelled the same section of road again and took notice of what happened.

I'd be interested if anyone else lives or travels around the Exeter area and might be able to check out how their car behaves at the same spot.

Travelling up Telegraph hill (anyone local will know it) towards Newton Abbot. I had the cruise set to 70MPH and around 2/3 of the way up it changed to 77MPH - this is the same section of road that the speed prviously changed to 85MPH

 

[Fursty Ferret]

Resurrecting this thread as today I travelled the same section of road again and took notice of what happened.

I'd be interested if anyone else lives or travels around the Exeter area and might be able to check out how their car behaves at the same spot.

Travelling up Telegraph hill (anyone local will know it) towards Newton Abbot. I had the cruise set to 70MPH and around 2/3 of the way up it changed to 77MPH - this is the same section of road that the speed prviously changed to 85MPH

Mine did this at Christmas. Didn’t think much of it until I saw this thread. Can’t remember what speed it increased to, but I do recall having to wind it back to 72.

Speed control has been ropey for a while, in particular the irritating habit of slowing to 40 or 50 (or trying to…) passing motorway junctions and the weird and violent pogoing down the road when following a slowly moving lead car at 5mph.

 

[MrBadger]

If you are inclined, may be worth checking that section in OpenStreetMap browser - OpenStreetBrowser - iirc you want infrastructure.

It’s not straightforward to use, but after fumbling around it sometimes reveals why a car speeds might change. I’ve used it to confirm an odd mapping speed discrepancy within the reduced 50mph M25/M3 transition where you have to wind it back to 50 from 70 for a couple 100 yards. You may need to go checking multiple lanes/nodes especially at junctions/intersections.

I’m not saying that is where Tesla get their mapping data from, but whatever their source is will be getting some data from common underlying sources. OpenStreetMap in UK use OS data for some (non speed) underlying data so there is a lot of mapping data that is consistent across whatever mapping source that you use.

I’ve never been convinced that Tesla take split levels into account when working out things which can explain wacky things at some intersections/flyovers.

And yes, the Tesla rollercoaster ride when on TACC/AP in a queue had been around for a while. I thought vision may have fixed that but it didn’t.

 

[GeorgeSymonds]

I was under the impression that it will change up and down but never above the initial set speed. Ie it will do 60 -> 50 -> 60 but not 50 -> 60 (or at least shouldn’t)

Something odd is happening for sure. You’re not in the path of a airfield radar or nuclear reactor are you? Or crossing a haunted Roman road? Or a Chinese hot air balloon is floating overhead?