Tests uncover issues for advanced features Some interesting highlights are below the Model S tested is a 2016 with 7.1 software and probably AP1 hardware. It did well except for hill crests. The Model 3 with AP2 did even better. The 2017 BMW 5-series with "Driving Assistant Plus," 2017 Mercedes-Benz E-Class with "Drive Pilot," 2018 Tesla Model 3 and 2016 Model S with "Autopilot" (software versions 8.1 and 7.1, respectively) and 2018 Volvo S90 with "Pilot Assist" were evaluated. All five have automatic emergency braking systems rated superior by IIHS. One series involved driving at 31 mph toward a stationary vehicle target with ACC off and autobrake turned on to evaluate autobrake performance. Only the two Teslas hit the stationary target in this test. The same test was repeated with ACC engaged and set to close, middle and far following distance in multiple runs. With ACC active, the 5-series, E-Class, Model 3 and Model S braked earlier and gentler than with emergency braking and still avoided the target. The cars slowed with relatively gradual decelerations of 0.2-0.3 gs, braking in the same manner no matter the distance setting. Braking before impact was earlier for the Teslas than for the 5 series and E-Class. . . . . A fourth scenario involved the test vehicle following a lead vehicle, which then changed lanes to reveal a stationary inflatable target vehicle in the path ahead when the time to collision was about 4.3 seconds. None of the vehicles crashed into the target, and the 5 series, E-Class and Teslas all braked earlier and gentler than the S90, similar to the active ACC test. . . .Out on the road, engineers noted instances in which each vehicle except the Model 3 failed to respond to stopped vehicles ahead. . . . Unnecessary or overly cautious braking is an issue IIHS noted in the Model 3. In 180 miles, the car unexpectedly slowed down 12 times, seven of which coincided with tree shadows on the road. The others were for oncoming vehicles in another lane or vehicles crossing the road far ahead. . . . Only the Model 3 stayed within the lane on all 18 trials. The Model S [with the older hardware and software] was similar but overcorrected on one curve, causing it to cross the line on the inside of the curve in one trial. None of the other systems tested provided enough steering input on their own to consistently stay in their lane, often requiring the driver to provide additional steering to successfully navigate the curve. The E-Class stayed within the lane in 9 of 17 runs and strayed to the lane marker in five trials. The system disengaged itself in one trial and crossed the line in two. The 5 series stayed within the lane in 3 of 16 trials and was more likely to disengage than steer outside the lane. The S90 stayed in the lane in 9 of 17 runs and crossed the lane line in eight runs. . . . The E-Class stayed in its lane in 15 of 18 trials and on the line in one trial, continuously providing steering support without erratic moves when lane lines weren't visible. The Model 3 also stayed in the lane in all but one trial, when it hugged the line. In contrast, the 5-series, Model S and S90 struggled. The 5-series steered toward or across the lane line regularly, requiring drivers to override the steering support to get it back on track. Sometimes the car disengaged steering assistance on its own. The car failed to stay in the lane on all 14 valid trials. The Model S was errant in the hill tests, staying in the lane in 5 of 18 trials. When cresting hills, the Model S swerved left and right until it determined the correct place in the lane, jolting test drivers. It rarely warned them to take over as it hunted for the lane center. The car regularly veered into the adjacent lanes or onto the shoulder.