Keeping on the right track

Imagine yourself in a life-or-death confrontation with an oncoming car, but as you turn the wheel away from danger the car wants to go back into the shooting line. It happened to me in Italy a while back, driving a then-new Mercedes-Benz CLS. And it was scary.

But it will never happen again, to me or anyone else, thanks to revisions to Benz's electronic lane-keeping assistant. In case you need a reminder, this safety technology is still on its way down to your car, the 'active' lane-keep assist is intended to intervene if it detects you wandering off the road. It's one of the latest electronic countermeasures to fight fatigue and distracted drivers.

At first, the lane-keeper system wobbled the steering wheel as if you were running over a string of cats eyes, then it moved on to a system which brakes the inside-front wheel to straighten the car for you. A bit like electronic stability control, with a twist. That's fine - unless you have deliberately eased away from danger and the car thinks you've dozed off.

The Carsguide crew reported the glitch to Benz after the CLS drama and, to the company's immense credit, it reacted quickly and positively. I was soon on a flight to Germany to re-create the situation on a frozen airfield and other journalists were quizzed about their experiences with the CLS, including one who had nearly bowled a motorcycle who was riding in the car's blind spot at the rear three-quarter.

Then, at the global preview of the flagship S-Class I am reminded of Benz's safety-first approach to motoring when a new-and-improved Active Lane Keeping Assist system is introduced, complete with revisions from the Carsguide experience. Instead of just checking to see if the driver is signalling a lane change, or that they are applying more than 10 degrees of lock on the wheel, it now uses front and rear scanners before activating the lane-keeper.

One system looks far ahead for a potential collision target and another looks behind to ensure there is nothing in the blind spots. It's great, because it's a good idea that just needed some tuning. Even better, Benz admits there was room for improvement - and that Carsguide triggered the changes. “Yes, you can claim the credit,” says Benz's latest safety guru, Jochen Haab, as I climb from the S-Class.

He explains the changes and the process, as well as the trickle-down effect that will take the system from the S-Class down into the E-Class and beyond - and even into other brands, as Mercedes-Benz has always been happy to share anything on the safety front. “It's a lot more intelligent now. It has the same name but it monitors a lot more inputs,” Haab says. “If we find these things, we incorporate them.”

This reporter is on Twitter: @paulwardgover