DETROIT – Take note of the facelift Daimler AG has given the ’12 Mercedes-Benz C-Class because you won’t likely see anything like it again. Not soon, anyway.

Boasting more than 2,000 components that differ from the ’11 model, the revised car marks “the most in-depth facelift we have ever done,” says Daimler CEO and Chairman Dieter Zetsche, who also heads the auto maker’s Mercedes-Benz car division.

“And I expect it to remain the most far-reaching,” he tells journalists at an event to preview the car before its world debut at the North American International Auto Show here today. At least in the near-term, he adds.

Mercedes is mum on the cost of the refresh, but the car brand’s global sales and marketing director says the auto maker had no choice but to be aggressive.

“We are very successful at the moment, but there are still three years to go” before the next-generation C-Class arrives, Joachim Schmidt tells Ward’s.

Upgrades include the introduction of Command Online, the auto maker’s new telematics platform, and 10 new safety technologies:

  • Adaptive Highbeam Assist
  • Active Lane-Keeping Assist
  • Active Blind Spot Assist
  • Attention Assist.
  • Distronic Plus
  • Speed-Limit Assist
  • PARKTRONIC parking assist
  • PRE-SAFE Brake
  • Lane-Keeping Assist
  • Blind Spot Assist

The car also benefits from standard-equipment light-emitting-diode daytime running lights.

Powertrain enhancements include a new 7-speed automatic transmission in the diesel-equipped C300 and C250 models with the brand’s 4MATIC all-wheel-drive system. Aesthetic changes include a restyled dashboard and bolder grille surround.

“The C-Class is for us, volume-wise, the most important car which we have,” Schmidt says.

Daimler reports worldwide deliveries of 250,600 units last year, an 11% jump from 2009’s total. U.S. sales outpaced the global trend with a 12.1% leap, according to Ward’s data. But the car’s 58,785 deliveries trailed the redesigned-for-’10 E-Class.

Sales of the larger car soared to 60,922 in 2010, a 41.4% gain on prior-year, according to Ward’s.

The auto maker says some 8.5 million C-Class cars have been sold globally since the model was introduced in 1982. Mercedes tallies more than 1 million sales of its current-generation model, which launched in 2007.

Mercedes begins taking orders for the C-Class today in Germany. The car, available there as a wagon or sedan, is expected to arrive on dealer lots in March.

The new C-Class is scheduled to be in U.S. showrooms in September. Sales will be limited to sedan models equipped with gasoline-powered V-6 engines, though the auto maker has said American customers will be able to order the next-generation car with a 4-cyl. diesel engine.