[Spyder3]

My 2018 540i xDrive has had an intermittent issue over a dozen times over the past year. I'm curious if others have also seen this problem? Has anyone had it resolved? I would love to be informed about how to get this repaired / resolved. Or maybe I'm doing something wrong? Please educate me.

The car has the 'Driving Assistance Plus Package' which includes active cruise control w/stop and go, active lane keeping assistant w/side collision avoidance, traffic jam assistant and evasion aid and cross-traffic alert front. I L-U-V this feature.

While driving on longer trips (over 300 miles on the highway and/or Interstate), and usually a few hours into the trip, the Active Cruise Control will suddenly stop working at speed. Multiple notifications pop up on the iDrive display. Upon notification, the cruise control is then inoperable, and cannot be re-activated for some time. On the last multi-day trip, this happened 4-5 times in one day, 3 times on another day, a single time on the last day. Other trips have exhibited similar issues. Sometimes not at all.

Most times, after 10-15 minutes, the system will reset itself and normal operation returns. Sometimes I need to turn off the car, exit and lock, then restart to return to normal. At least I got that going for me. But I have concerns because this is a safety issue as the Driving Assistance Plus features unexpectedly stop working while in motion, which I may need in a critical safety situation (e.g., collision with another vehicle or pedestrian/animal).

I have had the car into my local BMW service center 3 times to attempt resolution of this issue. Response has been; 1) unable to reproduce/no repair, 2) the tech saw fluctuations in voltage in the logs, replaced both 12v and 48v batteries under warranty, thank you, but the issue remains 3) technician notes the car is dirty and seems to be saying that's the issue; dirty sensors (car is at service center as I type).

I call BS on the car's hygiene, since it was freshly washed when the problem recurred on several occasions. Shame on me for having the car serviced while dirty.

Again, if you've seen this issue and can inform this group of status and outcomes, it would be most appreciated.

Loving my G30, except for this one (important) thing.

Thank you in advance for your insights and advice.

[claykin]

Has dealer done a software update? That's first thing they should do. From there when they scan codes they should see faults associated with the driver assist functions. Get it fixed before your warranty runs out. Most parts that are part of DA+ are very expensive.

[Spyder3]

Originally Posted by claykin

Has dealer done a software update? That's first thing they should do. From there when they scan codes they should see faults associated with the driver assist functions. Get it fixed before your warranty runs out. Most parts that are part of DA+ are very expensive.

Yep, software updates have been performed (last June and December). I'll ask again, thanks for the reminder.

Codes have been scanned and they can see the events (the tech is saying they are 'warnings' not 'errors'). Hmmm, we'll see where that goes.

And yes, anxious to see how warranty comes into play here. Service Advisor indicates since the problem was worked on while under warranty last year (expired December 2022), BMW _should_ honor warranty for needed repairs. We'll see.

[jsf721]

Clean the front sensors. Had this happen when lens was covered in slush.

[Volasko]

Originally Posted by Spyder3

My 2018 540i xDrive has had an intermittent issue over a dozen times over the past year. I'm curious if others have also seen this problem? Has anyone had it resolved? I would love to be informed about how to get this repaired / resolved. Or maybe I'm doing something wrong? Please educate me.

The car has the 'Driving Assistance Plus Package' which includes active cruise control w/stop and go, active lane keeping assistant w/side collision avoidance, traffic jam assistant and evasion aid and cross-traffic alert front. I L-U-V this feature.

While driving on longer trips (over 300 miles on the highway and/or Interstate), and usually a few hours into the trip, the Active Cruise Control will suddenly stop working at speed. Multiple notifications pop up on the iDrive display. Upon notification, the cruise control is then inoperable, and cannot be re-activated for some time. On the last multi-day trip, this happened 4-5 times in one day, 3 times on another day, a single time on the last day. Other trips have exhibited similar issues. Sometimes not at all.

Most times, after 10-15 minutes, the system will reset itself and normal operation returns. Sometimes I need to turn off the car, exit and lock, then restart to return to normal. At least I got that going for me. But I have concerns because this is a safety issue as the Driving Assistance Plus features unexpectedly stop working while in motion, which I may need in a critical safety situation (e.g., collision with another vehicle or pedestrian/animal).

I have had the car into my local BMW service center 3 times to attempt resolution of this issue. Response has been; 1) unable to reproduce/no repair, 2) the tech saw fluctuations in voltage in the logs, replaced both 12v and 48v batteries under warranty, thank you, but the issue remains 3) technician notes the car is dirty and seems to be saying that's the issue; dirty sensors (car is at service center as I type).

I call BS on the car's hygiene, since it was freshly washed when the problem recurred on several occasions. Shame on me for having the car serviced while dirty.

Again, if you've seen this issue and can inform this group of status and outcomes, it would be most appreciated.

Loving my G30, except for this one (important) thing.

Thank you in advance for your insights and advice.

I've noticed this a few times when we've had some big snow falls. I'm assuming you're just getting a build up of slush/snow/ice on the sensors while in motion. Once the sun or some heat gets on the car it melts off thus why it seems to fix itself.

[Spyder3]

OP here... to be clear, the failure occurs in clear weather, with a clean car. It makes sense the camera, radar and other sensors must be unobstructed to operate properly.

I'm trying to learn whether the failure is a common issue.

Glad to hear others don't seem to have this problem.

[admranger]

Originally Posted by Spyder3

OP here... to be clear, the failure occurs in clear weather, with a clean car. It makes sense the camera, radar and other sensors must be unobstructed to operate properly.

I'm trying to learn whether the failure is a common issue.

Glad to hear others don't seem to have this problem.

I'd ask them to ensure that all connectors are still water tight and plugged into the system completely/correctly. Only other thing I can imagine is a heat related issue of some sort? Seems though that intermittent and in good weather would point to a loss of connectivity to one of the sensor suites.

[LogicalApex]

Originally Posted by Volasko

I've noticed this a few times when we've had some big snow falls. I'm assuming you're just getting a build up of slush/snow/ice on the sensors while in motion. Once the sun or some heat gets on the car it melts off thus why it seems to fix itself.

Front radar is heated. So snow snd ice shouldn’t stop it unless extremely heavy.

But no warnings in the car if that heater fails. You’ll only get the reduced message in the car frequently in those cases.

If under warranty still I’d have the heater checked for the front radar.

[abnatelee]

It could be salt buildup too. Kicked up salt from vehicles in front of you can affect the radar sensors. To reduce that from happening, you can try cleaning the sensors and see if the code clears on its own.