2002 Mercedes-Benz ML500 recalls and problems

ODI opened the investigation based on reports that the subject vehicle brake lamp switch (switch) failure caused 1) inoperative brake lamps (stay on or fail to illuminate), and/or 2) shift interlock failure (shifter locked in park), and/or 3) the cruise control to fail to cancel with brake application.Consumers also reported the illumination of a warning lamp on the instrument panel.The switch contains three sets of electrical contacts and a (normally extended) spring loaded plunger that actuates the contacts as it moves.As installed in the vehicle, the plunger contacts the brake pedal arm and is pushed into the switch; as the driver applies the pedal the plunger extends.One set of contacts (BLS) operates the stop lamps, a second set (EWM) controls the shift interlock system, and a third set (BS) is used by an on-board diagnostic (OBD) system to monitor switch operation.The cruise control monitors the BLS signal to determine when the brake is applied, the primary way the system is disabled when set.The relative timing of contact actuation in response to plunger movement allows the OBD system to detect a switch fault.When a fault is detected a malfunction indication lamp (MIL) is illuminated (driver alert), a diagnostic trouble code (DTC) is stored (for the service technician), and cruise control operation is inhibited (as a failsafe).In its response to ODI's January 2011 information request letter, MB explained its assessment of switch failures which was based primarily on ev…

ANALYSIS OF COMPLAINTS TO ODI AND MERCEDES AND WARRANTY CLAIM DATA SUBMITTED BY MERCEDES INDICATES THAT THE ALLEGED DEFECT HAS OCCURRED AT A LOW RATE (36.5 COMPLAINTS PER 100,000 VEHICLES AND 0.29 PERCENT WARRANTY CLAIM RATE), WITH NO DISCERNABLE DEFECT TREND INDICATING THAT THE RATE OF CHAFING RELATED BRAKE LINE FAILURES IS INCREASING.THERE HAVE BEEN NO NEW COMPLAINTS SINCE JANUARY 2009.WHEN THE ANALYSIS IS LIMITED TO INCIDENTS OF BRAKE LINE LEAKAGE THAT RESULTED IN ALLEGATIONS OF REDUCED BRAKE EFFECTIVENESS, THE RATE DROPS EVEN FURTHER (22.3 COMPLAINTS PER 100,000 VEHICLES AND 0.04 PERCENT WARRANTY CLAIM RATE). MERCEDES PROVIDED DATA SHOWING THAT IN THE RARE INSTANCES WHEN CHAFING DID PROGRESS TO BRAKE LINE LEAKAGE THE DRIVER WOULD BE IMMEDIATELY ALERTED TO A PROBLEM BY ILLUMINATION OF THE BRIGHT YELLOW ESP/BAS WARNING LAMP AND CHANGES IN BRAKE PEDAL FEEL.CONTINUED OPERATION WITH A LEAKING BRAKE LINE WOULD RESULT IN ILLUMINATION OF THE BRIGHT RED BRAKE WARNING LAMP AND AN AUDIBLE CHIME DUE TO LOW MASTER CYLINDER RESERVOIR LEVEL. CONTINUED OPERATION WITH THE BRAKE WARNING LAMP ILLUMINATED WOULD ULTIMATELY DRAIN THE RESERVOIR FOR THE AFFECTED CIRCUIT, RESULTING IN LOSS OF THE CIRCUIT AND AN APPROXIMATELY 80% INCREASE IN STOPPING DISTANCES. SURVEYS CONDUCTED BY ODI AND VRTC INDICATE THAT ROUTING ANOMALIES MAY BE MORE COMMON THAN THE COMPLAINT AND WARRANTY DATA SUGGEST FOR THE SUBJECT LINE BUNDLE, WITH LINE CONTACT OR OTHER ROUTING ANOMALY NOTED IN 13 OF 51 VEHICLES SURVEYED BY…

MERCEDES-BENZ'S RESPONSE TO ODI'S INFORMATION REQUEST LETTER FOR PE08-002 INDICATED THAT THE SUBJECT FUEL/BRAKE LINE BUNDLE (PART NO. A1634201526) WAS USED WITHOUT SIGNIFICANT CHANGE FROM MODEL YEAR 1998 THROUGH 2002 ON ALL M-CLASS LIGHT TRUCK VEHICLES.MERCEDES FURTHER INDICATED THAT IN 2002 A PROBLEM WAS IDENTIFIED IN PRODUCTION THAT COULD CAUSE UNWANTED CONTACT BETWEEN THE FUEL AND BRAKE LINES.IN MAY 2002, A PRODUCTION ACTION WAS AUTHORIZED AS A RESULT OF POST-PRODUCTION INSPECTIONS OF VEHICLES EXHIBITING CONTACT BETWEEN THE FUEL AND BRAKE LINES.THE ACTION AUTHORIZED THE USE OF ADDITIONAL PLASTIC SPACER CLIPS TO ELIMINATE SUCH CONTACT.MERCEDES HAS INDICATED THAT CONTACT BETWEEN THE LINES IS MORE LIKELY IN VEHICLES EQUIPPED WITH V-8 ENGINES DUE TO LESS FREE SPACE IN THE ENGINE COMPARTMENT. ODIHAS RECEIVED ONE COMPLAINT FROM THE OWNER OF A MY2001 ML430 THAT WAS INVOLVED IN A CRASH BECAUSE OF SUDDEN LOSE OF BRAKE EFFECTIVENESS. INSPECTION OF THE VEHICLE AFTER THE CRASH SHOWED THAT THE LOSS OF BRAKING WAS THE DIRECT RESULT OF CHAFFING OF THE FUEL LINE ON THE BRAKE LINE THAT CAUSED THE SUDDEN LOSE OF BRAKE LINE PRESSURE WHEN COMING TO A NORMAL TRAFFIC STOP.THIS INVESTIGATION HAS BEEN UPGRADED TO AN ENGINEERING ANALYSIS (EA08-009) TO FURTHER ASSESS THE SCOPE, FREQUENCY AND POTENTIAL SAFETY CONSEQUENCES ASSOCIATED WITH THE RUPTURE OF THE FUEL LINE/BRAKE LINE BECAUSE OF CHAFFING IN ALL MERCEDES M-CLASS VEHICLES EQUIPPED WITH V-8 ENGINES.