One problem related to adaptive cruise control has been reported for the 2018 Porsche Cayenne. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2018 Porsche Cayenne based on all problems reported for the 2018 Cayenne.
2018 Porsche Cayenne: at highway speeds, randomly a serious unsafe to operate �service necessary� warning appears on the instrument panel and the cruise control malfunctions. With the service necessary warning indicated, the vehicle is unsafe to operate. This unsafe vehicle is not drivable with cruise control for approximately the next hour. This breakdown is known to Porsche (via their communications with me) and they are unable to rectify the error. In a 2020 Porsche Cayenne this failure has been rectified. Attached, invoices from five visits to Porsche dealerships, all during the warranty period. Attached also photographs taken on various days, times and speeds, and traffic conditions of the service necessary warning on instrument panel and cruise control malfunctions.