MISSOULA, MT – Just about anyone who has driven a Mercedes-Benz in the past decade has experienced it: unintended sudden acceleration because of awkward placement of the cruise-control stalk on the left side of the steering wheel.

A driver may think he is signaling to turn right, when inadvertently he has pushed the cruise control lever upward to the “accel” position, occasionally sending the vehicle bolting forward instead of slowing down to turn at an intersection. This could happen if the cruise control was on but not active.

Left turns were somewhat less problematic because pushing the lever downward put the cruise-control system into “decel” mode.

Nevertheless, with the all-new ’12 M-Class cross/utility vehicle going on sale in September, Mercedes has corrected the problem once and for all by placing the turn indicator at the 10 o’clock position and the cruise-control stalk at 8 o’clock.

Until now, those placements were reversed in virtually all Mercedes vehicles, triggering complaints.

The turn-indicator stalk, which also controls the windshield wipers and high-beam headlamps, is longer than the cruise-control lever, and Mercedes engineers are hopeful the new configuration will eliminate any confusion.

Bernie Glaser, general manager-product management for Mercedes-Benz USA, emphasizes the change in his presentation of the new M-Class to journalists here this week.

“A lot of research has been done,” he says. “Customer feedback went into that decision, and the M-Class is the first Mercedes where this has been changed.

You will see that change in our philosophy here coming with launches of other new models.”

Jim Burch, assistant product manager for the M-Class and GLK CUV, says the market drove the new layout.

“The comments were that there was some confusion with the cruise control,” Burch says.

“We wanted to address that issue, and this was the best solution based on testing with those consumers.”

Pricing starts at $48,990 for the ’12 ML350 4Matic, equipped with a new 302-hp direct-injection gasoline 3.5L V-6, while the improved 240-hp diesel ML350 BlueTEC 4Matic starts at $50,490.

Those prices include destination charges of $875 and are unchanged from the ’11 model year, while incorporating 3% more content.

A 4.6L BiTurbo V-8 version arrives in first-quarter 2012; the engine produces 429 hp in the CL550 4Matic coupe.

A 2-wheel-drive ML350 is expected in showrooms in September 2012.

The gasoline V-6 is anticipated to dominate the mix, while the diesel should constitute up to 20% of sales and the V-8 up to 10%, the auto maker says

Although a hybrid M-Class had been available with the previous generation, Mercedes officials say there are no plans for one in the near future.

Through the year’s first half, the outgoing M-Class has continued to sell well, notching 14,189 deliveries, up 14.5% compared with like-2010.

Of 17 vehicles in Ward’s Middle-Luxury CUV segment, the M-Class places fourth in sales behind only the Lexus RX, Cadillac SRX and BMW X5.

tmurphy@wardsauto.com