Two automakers have debuted hands-free driving systems in as many model years. First came GM’s Super Cruise, which bowed for 2018 on the Cadillac CT6 sedan. Super Cruise will soon join the new CT5 and CT4 sedans, and eventually other GM brands. Now, BMW joins the fray with Extended Traffic Jam Assistant, a system offered on the 2019 3 Series and 8 Series sedans, and the X5 and X7 SUVs. The redesigned X6 SUV and updated 7 Series sedan will also offer it for 2020.
Both systems monitor the driver to ensure he or she pays attention. Neither one relieves you of watching the road, something Audi touted its new Traffic Jam Pilot could facilitate in low-speed highway gridlock. But regulatory hurdles kept Audi from offering TJP in the U.S., leaving GM and BMW with the most capable semi-autonomous systems in a production vehicle this side of the Atlantic. We’ve tested Super Cruise before, but we haven’t had a substantive time to test ETJA on local roads — until now. And test it we did, this time in a 2019 X7 xDrive50i.
We evaluated ETJA in the X7 on the expressways around Cars.com’s Chicago offices, activating it umpteen times during rush-hour commutes, weekend road trips and more. Our impressions are decidedly mixed.
Prohibitive Parameters
ETJA works only on limited-access highways with physical barriers to oncoming traffic, like a median, and clearly marked exits and entrances. The system intuits such conditions through GPS, cameras and radar, but it isn’t the only prerequisite for activation. ETJA must also detect wide enough lanes, no pedestrians and a car in front of you, BMW spokesman Oleg Satanovsky told Cars.com in an email. A driver-facing camera intuits you’re paying attention, and the system works at speeds up to around 40 mph — the latter a major difference versus Super Cruise, which works all the way up to highway speeds.
Asked why the speed threshold is so low, Satanovsky acknowledged that BMW’s approach “may be more conservative” but defended it as a safety measure. He declined to say whether the hardware is capable of higher speed thresholds through an over-the-air update later on.
Multiple editors bemoaned the 40 mph ceiling. The operating conditions “are so limited, I wonder what the advantage is, short of reducing driver fatigue slightly and getting drivers familiar with the technology,” Executive Editor Joe Wiesenfelder said.
Even within the acceptable speed, the many events that can trigger deactivation make ETJA’s operation downright sparse.
The system “demands a good deal of your attention because of its propensity to disengage, requiring you to take hold of the steering wheel again,” Senior Editor Mike Hanley said. “The system repeatedly disengaged during my testing — it only remained active for a few minutes at a time during the rush-hour crawl — and it was often unclear what had made the system deactivate.”
Tough to Turn On
Several staffers noted the system doesn’t make itself easy to reactivate, or even turn on in the first place. As this video from BMW details, drivers activate the system through two steering-wheel buttons. Associated LEDs on the steering wheel, plus a message on a dashboard display, indicate when ETJA is available to use — but such indications are fleeting.
“The hands-free capability was available shortly after entering the expressway but it was at times difficult to activate,” Hanley said. “It seemed like if you didn’t react quickly enough to the instrument cluster message indicating the system was available, it wouldn’t let you engage it until the message appeared again.”
Managing Editor Joe Bruzek echoed Hanley’s frustration.
“The biggest annoyance was activation,” Bruzek said. “It would communicate that it’s ready, but I couldn’t activate quickly enough before its parameters were suddenly not met and I was locked out of the system.”
Icons to indicate system activity confused some editors, too. Bruzek noted that the “displayed graphics also aren’t very telling of what to do,” and Wiesenfelder noted the icons for ETJA and a lesser mode, which still centers the vehicle but requires your hands on the wheel, aren’t distinct enough within the gauges.
Intervention Required
BMW’s Satanovsky cautioned that the driver remains “always responsible for control of the vehicle” with ETJA. Our experience proved that point time and again.
Hanley noted “occasionally poor lane-following behavior,” with a “couple of times when I had to take over control of the steering because the X7 was getting too close to traffic next to me; in one instance the X7 was about to cross the lane markings without, it seemed, any recognition that they were there.”
Editor Jennifer Geiger found “little finesse when it came to centering the car within the lane; there was too much ping-ponging from side to side.”
And several editors noted a familiar problem with adaptive cruise control systems industrywide: the need to hit the brakes, which deactivates ETJA and other ACC systems, when other cars merge too closely ahead.
Eye Spy
ETJA’s driver-facing camera monitors your nose and eyes to make sure you’re facing forward with eyes open, Satanovsky said. But the camera sits in the instrument display, a vantage blocked by the steering-wheel rim if you drive with the column tilted low. That happened to Wiesenfelder and Hanley.
“A warning on the dashboard screen suggested moving the steering wheel or the seat so the sensor wasn’t blocked,” Hanley elaborated. “I only had to move the steering wheel up slightly to provide the sensor with its needed line-of-sight and get the system working again, but it was still annoying to have to change my driving position to accommodate it.”
The driver-facing camera for Super Cruise, by contrast, sits on the steering column. Adjust the wheel and it moves, too.
But When It Works …
For all its annoyances, editors lauded ETJA when it did work. Geiger thought it “did a good job of accelerating and decelerating smoothly and predictably,” while Hanley deemed the system superior to Super Cruise in centering the car. Polarized sunglasses didn’t interfere with the camera’s ability to see your eyes, and glances at the dashboard touchscreen didn’t set off inattention alarm bells.
Bruzek said the system works “astonishingly well” once all systems are go.
“I felt immediately comfortable using the [ETJA] mode,” he said. “It confidently centered in the lane, kept a comfortable distance from the car ahead and for me.”
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