ACC cutting out intermittently

[Joules]

Has anyone out there had the ACC switch off while engaged It seems to do it randomly and is easily switched back on, but has only just started doing it after a software update to cure the bluetooth pairing problem. I took it back to the dealer and he took it for a hurl and annoyingly it didn't happen. I also notice that since update selecting the speed can be increased/decreased by a single touch of the left hand button, if you hold it for slightly longer it goes up/down in multiples of 5mph. This is the reverse of what it used to be. I've got used to now.

 

[AdyC]

Mine does this since the software update but it only happens when a large vehicle comes towards me on the opposite side of the road It also starts to slow done prior to this with noticeable braking but not aggresive.

 

[craigupnorth]

Mine does this since the software update but it only happens when a large vehicle comes towards me on the opposite side of the road It also starts to slow done prior to this with noticeable braking but not aggresive.

Yeah - this behaviour is frustrating. Car sees a truck coming with lights up high (or whatever it is that triggers it), seems to get confused /scared, and slows down … silly car …

 

[Joules]

Mine does this since the software update but it only happens when a large vehicle comes towards me on the opposite side of the road It also starts to slow done prior to this with noticeable braking but not aggresive.

Since I posted this, I've been noting where it does it most. On my home, I follow the same route and in the same spot it has cancelled itself 4 out of the last 5 times. It's a quiet rural road with some overhanging trees, I wonder if it's that. I'll make a mental note to look at the trees and there position. I wonder if it's a shadow cast by the trees. Yes indeed...silly car

 

[NLMGSAN]

It started on mine also after the lka update (and anything that came with it). I do not consider it as coincidental. It happens when I get squeezed between two lorries (3 lanes, me in the middle). It also happened when I had a light flick at the wheel while closing in to the lane marker, and another car quickly approaching me on the left side. Though quality is poor, I have two occasions on camera.

In fact, it coincides with sudden interventions at the wheel when going back to the previous lane with indicator on. This disappears with LKA off. And with TJA on and LKA off, it also does not happen anymore. Yet, TJA does use the LKA system....

To me this just shows the multiple modules, when not correctly adjusted and aligned, are not supporting me at all

 

[Joules]

It started on mine also after the lka update (and anything that came with it). I do not consider it as coincidental. It happens when I get squeezed between two lorries (3 lanes, me in the middle). It also happened when I had a light flick at the wheel while closing in to the lane marker, and another car quickly approaching me on the left side. Though quality is poor, I have two occasions on camera.

In fact, it coincides with sudden interventions at the wheel when going back to the previous lane with indicator on. This disappears with LKA off. And with TJA on and LKA off, it also does not happen anymore. Yet, TJA does use the LKA system....

To me this just shows the multiple modules, when not correctly adjusted and aligned, are not supporting me at all

Squeezed between two trucks.
So it's not just me then, On my way out following my rural route the other day I made note of the surroundings where the ACC disengages, I noticed an overhanging tree which is really some size. Its limbs stretch right across the road. Maybe it's shadow casting on the camera, maybe the same sort of thing with two trucks either side. Scary! Certainly since the update to -1300R40. Is that the same version you have

 

[siteguru]

It started on mine also after the lka update (and anything that came with it). I do not consider it as coincidental. It happens when I get squeezed between two lorries (3 lanes, me in the middle). It also happened when I had a light flick at the wheel while closing in to the lane marker, and another car quickly approaching me on the left side. Though quality is poor, I have two occasions on camera.

In fact, it coincides with sudden interventions at the wheel when going back to the previous lane with indicator on. This disappears with LKA off. And with TJA on and LKA off, it also does not happen anymore. Yet, TJA does use the LKA system....

To me this just shows the multiple modules, when not correctly adjusted and aligned, are not supporting me at all

Only in the sense that it uses the same sensors ... the software coding for TJA shares nothing with LKA. (To my belief, otherwise TJA wouldn't work when LKA was disabled).

 

[NLMGSAN]

Only in the sense that it uses the same sensors ... the software coding for TJA shares nothing with LKA. (To my belief, otherwise TJA wouldn't work when LKA was disabled).

I would say it shares hardware and parts of the software. But LKA, particularly the most sophisticated mode ELK, also uses input from other sensored systems (such as at the side and rear).

 

[NLMGSAN]

Squeezed between two trucks.
So it's not just me then, On my way out following my rural route the other day I made note of the surroundings where the ACC disengages, I noticed an overhanging tree which is really some size. Its limbs stretch right across the road. Maybe it's shadow casting on the camera, maybe the same sort of thing with two trucks either side. Scary! Certainly since the update to -1300R40. Is that the same version you have

No. Mine is r63. But we both have the latest LKA update.
Thing is: even if a real tree would be in front of your nose, ACC would support you to reduce speed and come to a standstill. But the car should not ACC.

 

[dave99]

I experienced this ACC dropout several times over the past weekend - on the motorway it would be active for quite a while then just turn off with no notice, I mean it could at least bong and flash something at me. I don't recall anything out of the ordinary when it dropped out, just in a lane following the car in front.

I did have the LKA updates last December but don't use ACC that much, probably did use it over the summer on a trip down to south wales and never had a problem then, and its not easily reproducible now - just seems random. Another thing to add to the list when it goes in for service

 

[Joules]

I experienced this ACC dropout several times over the past weekend - on the motorway it would be active for quite a while then just turn off with no notice, I mean it could at least bong and flash something at me. I don't recall anything out of the ordinary when it dropped out, just in a lane following the car in front.

I did have the LKA updates last December but don't use ACC that much, probably did use it over the summer on a trip down to south wales and never had a problem then, and its not easily reproducible now - just seems random. Another thing to add to the list when it goes in for service

Mine is still doing it and the software is now at version R67. Haugh's have test driven a few times, but can't get it to do it.
I drove up to Kinloch Rannoch with the ACC engaged for most of the time and it did it once on the A9 with over hanging trees and shadows. It still does it in the same place, as described earlier.