Active cruise control - keeps turning rear passenger interior lights on

[OldGrayOne]

Hi,

Car details 420d M Sportplus with active cruise control
2 months old - October 2016
4000 miles

BMW have already had this back under warranty and replaced the telematics control unit last week to fix the issues the car had with connected drive. All the connected systems are working correctly now but I'm left with the intermittent problem of the interior rear passenger lights coming on at random intervals.

As far as I can tell it is linked to using cruise control. This model has the active cruise control which I use all the time on the UK's congested motorways (it's reaction times are way better than mine!). After about 10 miles or so I'll look over my shoulder and notice that one of the rear interior lights is on. I'll turn it off and then about 10 miles later another one will be on. It is either the left or right side light not the brighter middle light. I've never noticed this happen when I don't use ACC and it happens any time of day. My only thought on cause and effect is that it might be triggered when the brakes are applied fairly hard (if someone darts into a gap in front of me) but that is just a theory at the moment.

It gets a bit annoying on a long drive to have to keep reaching back to turn them off so I will be taking it back to BMW to get sorted.

Since they have already had the vehicle for 6 days out of the 10 weeks I've owned this car (from new) I'm hoping someone has encountered something similar before!

Thanks in advance
Graham

[njp9677]

Diid you ever get to the bottom of this issue? My car does exactly the same thing and the BMW dealership have no clue how to fix it!

Thanks

Hi,

Car details 420d M Sportplus with active cruise control
2 months old - October 2016
4000 miles

BMW have already had this back under warranty and replaced the telematics control unit last week to fix the issues the car had with connected drive. All the connected systems are working correctly now but I'm left with the intermittent problem of the interior rear passenger lights coming on at random intervals.

As far as I can tell it is linked to using cruise control. This model has the active cruise control which I use all the time on the UK's congested motorways (it's reaction times are way better than mine!). After about 10 miles or so I'll look over my shoulder and notice that one of the rear interior lights is on. I'll turn it off and then about 10 miles later another one will be on. It is either the left or right side light not the brighter middle light. I've never noticed this happen when I don't use ACC and it happens any time of day. My only thought on cause and effect is that it might be triggered when the brakes are applied fairly hard (if someone darts into a gap in front of me) but that is just a theory at the moment.

It gets a bit annoying on a long drive to have to keep reaching back to turn them off so I will be taking it back to BMW to get sorted.

Since they have already had the vehicle for 6 days out of the 10 weeks I've owned this car (from new) I'm hoping someone has encountered something similar before!

Thanks in advance
Graham