Mercedes voluntarily issued a recall for 2000-2002 M-Class and 2000-2004 M-Class AMG vehicles due to a faulty brake lamp switch that could affect drivers' ability to disengage cruise control.
The National Highway Traffic and Safety Administration investigated Mercedes in September 2010 in response to a driver's complaint about the M-Class's faulty cruise control. The safety organization found that brake lamp switch failures could potentially affect the system under certain braking circumstances.
In some M-class SUVs, drivers can disengage the vehicle cruise control system using the cruise control stalk, or by braking quickly with either significant force or by tapping the brakes. However, some methods of braking, like pumping the brakes, can create a brake booster vacuum. The brake booster vacuum causes the brake lamp switch to become immovable, and could fail to disengage cruise control. At that point, you'd still be able to stop the car by applying significant pressure on the brakes or by using the cruise control stalk. But when the vehicle doesn't behave the way the driver expects, it could delay driver response and increase the risk of an accident.
Mercedes will recall the vehicles and replace the brake lamp switch. A total of 136,751 vehicles could be affected by this defect. M-Class owners can expect a notice in the mail from their dealers around September 2011.