IllustrationSEAT HEATER MALFUNCTIONED AND DRIVER'S SEAT CAUGHT ON FIRE.*AK
2001 Mercedes Benz ML320
Owner reports · Recalls · Investigations
More warning signs than most ML320 years
Owner complaints for the 2001 Mercedes Benz ML320 are substantially higher than the model-year median of 28.
About this comparison →How this year compares
Owner complaints by model year
Compare all ML320 years →Counts vary with age, sales and reporting. They are not failure rates.
What owners reported most
All reported categories
Tap a category to read its complaints. One report may name several components.
When problems were reported
Mileage at the reported incident
130–25K
1125–50K
1950–75K
2075–100K
22100–150K
23150K+
108 reports with mileage · 28 unknown
NHTSA’s mileage field refers to the reported incident, not necessarily the filing date. This shows report counts, not the likelihood of a failure.
What to inspect
Issues worth paying extra attention to based on owner reports.
- Electronic Stability Control (esc). Review the 33 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Service Brakes. Review the 26 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Steering. Review the 25 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
NHTSA owner reports · September 18, 2026 snapshot.
10 crash reports7 fire reports6 injury reports
What owners actually said
136 reports3RD CATALYTIC CONVERTER FAILURE IN LESS THAN A YEAR. DECEMBER, 2003 - INITIAL FAILURE. HAD TO BADGER MB TO FIND A PART. FUMES COMING IN TO THE CABIN OF THE VEHICLE. JUNE, 2004 - SECOND FAILURE OF CATALYTIC CONVERTER. OCTOBER, 2004 - CATALYTIC CONVERTER FAILED AGAIN. DUE THE NUMBER OF FAILURES ON THIS VEHICLE (IN ADDITION…
Read full complaint
3RD CATALYTIC CONVERTER FAILURE IN LESS THAN A YEAR. DECEMBER, 2003 - INITIAL FAILURE. HAD TO BADGER MB TO FIND A PART. FUMES COMING IN TO THE CABIN OF THE VEHICLE. JUNE, 2004 - SECOND FAILURE OF CATALYTIC CONVERTER. OCTOBER, 2004 - CATALYTIC CONVERTER FAILED AGAIN. DUE THE NUMBER OF FAILURES ON THIS VEHICLE (IN ADDITION TO THE CATALYTIC CONVERTER), REQUESTED FROM THE DEALER THAT WE SPEAK TO THE AREA MERCEDES-BENZ REPRESENTATIVE. DEALER REFUSED. INITIALLY BROUGHT TO THE ATTENTION OF THE DEALER ON OCTOBER 11TH. SCHEDULED FOR REPAIR ON OCTOBER 23RD. CONSIDERING THE POSSIBILITY OF ENGINE FUMES (AGAIN) , WE CONSIDER THIS A SAFETY ISSUE AS WELL AS AN ENVIRONMENTAL ISSUE. *JB
WHILE DRIVING AT HIGHWAY SPEEDS VEHICLE STALLED. CONSUMER HAD THE VEHICLE TOWED. DEALERSHIP INFORMED THE CONSUMER THAT THE PROBLEM PERTAINED TO THE FUEL PUMP MODULE, BUT THE PROBLEM HAD NOT BEEN RESOLVED. *AK
WHILE PULLING OUT OF A GAS STATION THE DRIVERS SIDE DOOR CAME OPEN. DEALER EXAMINED THE VEHICLE AND FOUND THAT THE DOOR LOCK WAS DEFECTIVE. A NEW DOOR LOCK WAS REPLACED ON DRIVERS SIDE.*AK *NM
I OWN A MERCEDES ML 320, 2001 MODEL. THE VEHICLE HAS HAD REPEATED FAILURES SINCE I PURCHASED IT NEW. THE VEHICLE IS NOW THREE YEARS OLD AND HAS 5700-0 MILES ON IT. THE MOST SERIOUS FAILURES INVOLVE THE FUEL PUMP ON THIS VEHICLE. THE FUEL PUMP HAS FAILED TWICE, WITH THE MOST RECENT FAILURE BEING 11/13/03. LARGE AMOUNTS OF GA…
Read full complaint
I OWN A MERCEDES ML 320, 2001 MODEL. THE VEHICLE HAS HAD REPEATED FAILURES SINCE I PURCHASED IT NEW. THE VEHICLE IS NOW THREE YEARS OLD AND HAS 5700-0 MILES ON IT. THE MOST SERIOUS FAILURES INVOLVE THE FUEL PUMP ON THIS VEHICLE. THE FUEL PUMP HAS FAILED TWICE, WITH THE MOST RECENT FAILURE BEING 11/13/03. LARGE AMOUNTS OF GAS FUMES FILL THE PASSENGER COMPARTMENT AND A SERIOUS DANGER OF EXPLOSION EXIST. THE FUEL PUMP LOCATION FOR THIS MODEL IS UNDERNEATH THE REAR PASSENGER SEAT AND DIRECTLY UNDER WHERE MY CHILDREN SIT. MERCEDES BENZ HAS BEEN AWARE OF THE FUEL PUMP PROBLEMS FOR UPWARDS OF FIVE YEARS AND HAVE FAILED TO CORRECT IT OR ACKNOWLEDGE A PROBLEM WITH IT. NO RECALL OR NOTICES TO THE CONSUMER. IN ADDITION THE ML 320 MODEL HAS A LONG LIST OF OTHER EMISSION FAILURES AND OVERALL FAILURES. THE FUEL PUMP IS THE MAIN ITEM FOR MY COMPLAINT AND IS A HUGE SAFETY ISSUE THAT SHOULD BE LOOKED INTO AS WELL AS THEIR REFUSAL TO ADDRESS THE ISSUE OR ACKNOWLEDGE IT. OTHER FAILURES AND ISSUES ON MY CAR INCLUDE: O-2 SENSOR, FUEL FILTER, PREMATURE WEAR AND REPLACEMENT OF BRAKE PADS (FRONT AND BACK), STEERING PROBLEMS, THROTTLE STICKING AT TAKE OFF (AT TIMES), WINDOW MOTOR, DRIVERS SIDE. SWITCH AS FAILED TWICE IN 57K MILES AND REASON IS SWITCH IS UNABLE TO HANDLE DESIGNED AMPERAGE. ALSO A POTENTIAL FIRE HAZARD. NO RECALL OR NOTICE AND A REPEATED KNOW PART FAILURE FOR THIS MODEL YEAR AND OTHER MODEL YEARS, REAR EMISSION EVAPORATOR PART. ALSO RELATED TO GAS FUMES IN THE INTERIOR OF THE VEHICLE AND COMMON FAILURE ITEM. (PART NAME IS NOT CORRECT TERMINOLOGY), BATTERY FAILURE WITHIN ONE YEAR, BATTERY NOT DESIGNED FOR AMPERAGE LOAD EITHER AND COMMON FAILURE. ALSO AS FIRE RISK., NUMEROUS OTHER FAILURES THAT ARE NOT ENTIRELY SAFETY RELATED FOR THIS PRODUCT., A SERIOUS LOOK INTO THIS VEHICLE AND THE COMPANIES ACTIONS REGARDING THESE REPEATED FAILURES OF FUEL RELATED ITEMS AND OTHER ITEMS IS NEEDED AND REQUESTED.*AK *TR
VEHICLE WAS REPAIRED UNDER RECALL 03V121000 CONCERNING POWER STEERING HOSE CLAMP. AFTER THE REPAIRS WERE DONE, THE VEHICLE LOST POWER STEERING WHILE DRIVING 55 MPH DUE TO A CLAMP FAILURE. THIS DEMONSTRATED THAT RECALL REMEDY WAS INADEQUATE.*AK AFTER THE RECALL FAILURE, THE CONSUMER LEARNED MERCEDES REDESIGNE…
Read full complaint
VEHICLE WAS REPAIRED UNDER RECALL 03V121000 CONCERNING POWER STEERING HOSE CLAMP. AFTER THE REPAIRS WERE DONE, THE VEHICLE LOST POWER STEERING WHILE DRIVING 55 MPH DUE TO A CLAMP FAILURE. THIS DEMONSTRATED THAT RECALL REMEDY WAS INADEQUATE.*AK AFTER THE RECALL FAILURE, THE CONSUMER LEARNED MERCEDES REDESIGNED THE CLAMP THREE TIMES. THE CLAMP USED ON THE CONSUMER'S VEHICLE WASN'T THE SAME CLAMP BEING USED THROUGHOUT THE RECALL. MERCEDES WAS CONTINUING TO MODIFY THE CLAMPS. CONSUMER NOTED THAT THE RECALL SHOULD BE RECALLED AGAIN. STEERING WAS LOST WITHOUT NOTICE AND WHICH WAS UNACCEPTABLE. *PH *JB
ENTIRE VEHICLE ELECTRICAL SYSTEM BURNED.*MR THE CONSUMER STATED THE VEHICLE CONTINUED EXPERIENCE ELECTRICAL PROBLEMS. *TS *JB
THE THIRD ROW SEAT BELT WOULD NOT RELEASE FOR MORE ROOM. WHEN CONSUMER TRIES TO MAKE MORE ROOM THE SEAT BELT WOULD GET TIGHTER, CAUSING BRUISES TO APPEAR ON THE CHILDREN'S NECKS. DEALERSHIP WAS NOTIFIED, BUT THE PROBLEM WAS NOT RESOLVED.*AK
WHILE DRIVING AT 20 MPH, THE VEHICLE CAUGHT ON FIRE, SMOKE AND FLAMES CAME FROM THE DASHBOARD. THE DEALER REPLACED ALL ELECTRICAL COMPONENTS, BUT THE VEHICLE STILL HAD ELECTRICAL PROBLEMS. *AK THE ELECTRICAL SYSTEM BURNED OUT WHILE DRIVING. THE LIGHTS CAME ON CONSTANTLY, THE AIR BAG LIGHT WOULD STATE THE AIR BAG WAS OFF,…
Read full complaint
WHILE DRIVING AT 20 MPH, THE VEHICLE CAUGHT ON FIRE, SMOKE AND FLAMES CAME FROM THE DASHBOARD. THE DEALER REPLACED ALL ELECTRICAL COMPONENTS, BUT THE VEHICLE STILL HAD ELECTRICAL PROBLEMS. *AK THE ELECTRICAL SYSTEM BURNED OUT WHILE DRIVING. THE LIGHTS CAME ON CONSTANTLY, THE AIR BAG LIGHT WOULD STATE THE AIR BAG WAS OFF, THE ALARM WOULD GO OFF CONSTANTLY IN THE DRIVEWAY, WHEN THE BRAKES WERE OFF, THE VEHICLE BEEPED. THE DEALER CLAIMED THEY WERE UNABLE TO FIND ANYTHING WRONG. *SCC *JB
I PICKED THIS NOTE UP FROM A MERCEDES-BENZ INTEREST GROUP WEBSITE, AND EXAMINED MY ML320, AND FOUND THIS TO BE A TRUE DANGER (TICKING TIME BOMB). HERE: DON'T KNOW IF THIS HAS BEEN A SUBJECT OF DISCUSSION BEFORE, SO FORGIVE ME IF IT HAS, I'M NEW HERE. I'M A DEALERSHIP TECHNICIAN IN SOUTHERN CA, AND I SEE A LOT OF THE ROU…
Read full complaint
I PICKED THIS NOTE UP FROM A MERCEDES-BENZ INTEREST GROUP WEBSITE, AND EXAMINED MY ML320, AND FOUND THIS TO BE A TRUE DANGER (TICKING TIME BOMB). HERE: DON'T KNOW IF THIS HAS BEEN A SUBJECT OF DISCUSSION BEFORE, SO FORGIVE ME IF IT HAS, I'M NEW HERE. I'M A DEALERSHIP TECHNICIAN IN SOUTHERN CA, AND I SEE A LOT OF THE ROUTINE FAILURES ON ALL OF THE MODELS. MOST OF THE TIME, WHEN SOMETHING SAFETY RELATED IS A REPEAT OR COMMON FAILURE ON A CAR, THERE IS A RECALL OR A CAMPAIGN ON THE ISSUE. NOT THIS TIME. FOR THE LAST FEW YEARS, I HAVE BEEN SEEING 163'S WITH CHAFED FUEL AND BRAKE LINES. NOW THERE'S TWO VERY IMPORTANT SYSTEMS ON ANY VEHICLE, FUEL AND BRAKES. THE TYPICAL FAILURE IS DIRECTLY BELOW THE MASTER CYLINDER AT THE FOREMOST BRAKE LINE. THE ONLY FUEL LINE RESTS INNOCENTLY AGAINST THE LINE, CHAFING AND RUBBING FOR MANY MILES. NOW, YOU WOULD THINK, OK, IT'S A RUBBER HOSE ON A METAL LINE, NO BIG DEAL, RIGHT? NO! THE FUEL LINE IS LINED WITH BRAIDED STAINLESS STEEL, WHICH EFFECTIVELY CUTS INTO THE BRAKE LINE. I HAVE PERSONALLY REPLACED SEVERAL BRAKE/FUEL LINE COMBOS ON THESE VEHICLES, AND SEEN MANY OTHERS DO THE SAME. ANY TIME I SEE IT, I REPLACE THE LINES, AND BRING IT TO THE ATTENTION OF HIGHER-LEVEL PERSONNEL IN MB, BUT TWO YEARS FROM THE FIRST ONE I HAD SEEN, THERE HAS NOT BEEN TO DATE (TO THE BEST OF MY KNOWLEDGE) ANY RECOGNITION OF THIS FAILURE BY MB CORPORATE. MORE COMMON ON ML 55, 500, 430 UP TO 2003. THEY SEEM TO HAVE SHORTENED THE FUEL LINE ON THE NEWEST VEHICLES. IF I COME ACROSS ONE SOON, I'LL TRY TO TAKE A PICTURE TO GIVE YOU FOLKS AN IDEA OF WHAT I'M TALKING ABOUT. A FRIEND WORKED ON ONE OUT OF STATE THAT HAD COMPLETE BRAKE FAILURE, AND THE WOMAN DRIVING ENDED UP GOING THROUGH A STOPLIGHT. I'LL CHECK IN ONCE IN A WHILE, IF ANYONE HAS ANY QUESTIONS I'LL DO MY BEST TO ANSWER THEM. JUST A HEADS-UP, DO YOURSELF A FAVOR AND GO LOOK AT YOUR ENGINE FUEL LINE. *LA
Official recalls
0No recalls in this snapshot.
Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗
NHTSA investigations
3PE10050 · Brake Lamp Switch Failure.
Opened Dec 21, 2010 · Closed May 4, 2011
Status: closed (inferred from source dates) · Exterior Lighting:brake Lights:switch; Service Brakes, Hydraulic; Vehicle Speed Control; Vehicle Speed Control:cruise Control
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 evaluation of field return failures.MB identified both 1) electrical contact and 2) mechanical switch failure mechanisms.According to MB's analysis, electrical contact failure is the predominate failure type and the failure consequence depends on which contact fails.For instance MB claims that BLS contact failures are momentary in nature and do not affect brake light operation but are nonetheless detected by the OBD system, resulting in a DTC and subsequent replacement.Electrical contact failures of the BS and EWM contacts result in a DTC also, and EWM contact failures result in the shifter being stuck in the park (which can be overridden by the consumer).Accordingly MB maintains that electrical contact failures of the switch have no safety consequence since the brake lamps remain operational and the cruise control is always disabled.MB determined that mechanical failures of the switch, which are rare in their assessment, can result from internal wear and/or increased switch operating temperatures.High temperatures occur due to overheating of the BLS contacts and can cause the internal plastic components to melt.In one scenario overheated BLS contacts may melt to the extended plunger and are damaged when the brake pedal is released resulting in the brake lights staying on.In another scenario the increased temperatures and/or internal wear can cause the plunger to stick in the fully depressed position.In this case the cruise may not cancel when the brake is applied and the driver may have to use high brake pedal forces or other means (shifting to neutral or using the cruise master switch) to disengage the cruise.Additionally the vacuum assist can be depleted if the driver pumps the brakes resulting in reduced braking effectiveness and even higher pedal forces.In its March 31, 2011 defect notification, MB stated that to remediate the potential need for excessive brake force it would conduct a safety recall (11V-208) to replace the switch with a more robustly designed component.The recall includes 136,751 model year 2000 - 2002 M-Class and model year 2000 - 2004 M-Class AMG vehicles.Owner notification letters will be mailed
Additional source detail variants (4)
Exterior Lighting:brake Lights:switch
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 evaluation of field return failures.MB identified both 1) electrical contact and 2) mechanical switch failure mechanisms.According to MB's analysis, electrical contact failure is the predominate failure type and the failure consequence depends on which contact fails.For instance MB claims that BLS contact failures are momentary in nature and do not affect brake light operation but are nonetheless detected by the OBD system, resulting in a DTC and subsequent replacement.Electrical contact failures of the BS and EWM contacts result in a DTC also, and EWM contact failures result in the shifter being stuck in the park (which can be overridden by the consumer).Accordingly MB maintains that electrical contact failures of the switch have no safety consequence since the brake lamps remain operational and the cruise control is always disabled.MB determined that mechanical failures of the switch, which are rare in their assessment, can result from internal wear and/or increased switch operating temperatures.High temperatures occur due to overheating of the BLS contacts and can cause the internal plastic components to melt.In one scenario overheated BLS contacts may melt to the extended plunger and are damaged when the brake pedal is released resulting in the brake lights staying on.In another scenario the increased temperatures and/or internal wear can cause the plunger to stick in the fully depressed position.In this case the cruise may not cancel when the brake is applied and the driver may have to use high brake pedal forces or other means (shifting to neutral or using the cruise master switch) to disengage the cruise.Additionally the vacuum assist can be depleted if the driver pumps the brakes resulting in reduced braking effectiveness and even higher pedal forces.In its March 31, 2011 defect notification, MB stated that to remediate the potential need for excessive brake force it would conduct a safety recall (11V-208) to replace the switch with a more robustly designed component.The recall includes 136,751 model year 2000 - 2002 M-Class and model year 2000 - 2004 M-Class AMG vehicles.Owner notification letters will be mailed
Service Brakes, Hydraulic
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 evaluation of field return failures.MB identified both 1) electrical contact and 2) mechanical switch failure mechanisms.According to MB's analysis, electrical contact failure is the predominate failure type and the failure consequence depends on which contact fails.For instance MB claims that BLS contact failures are momentary in nature and do not affect brake light operation but are nonetheless detected by the OBD system, resulting in a DTC and subsequent replacement.Electrical contact failures of the BS and EWM contacts result in a DTC also, and EWM contact failures result in the shifter being stuck in the park (which can be overridden by the consumer).Accordingly MB maintains that electrical contact failures of the switch have no safety consequence since the brake lamps remain operational and the cruise control is always disabled.MB determined that mechanical failures of the switch, which are rare in their assessment, can result from internal wear and/or increased switch operating temperatures.High temperatures occur due to overheating of the BLS contacts and can cause the internal plastic components to melt.In one scenario overheated BLS contacts may melt to the extended plunger and are damaged when the brake pedal is released resulting in the brake lights staying on.In another scenario the increased temperatures and/or internal wear can cause the plunger to stick in the fully depressed position.In this case the cruise may not cancel when the brake is applied and the driver may have to use high brake pedal forces or other means (shifting to neutral or using the cruise master switch) to disengage the cruise.Additionally the vacuum assist can be depleted if the driver pumps the brakes resulting in reduced braking effectiveness and even higher pedal forces.In its March 31, 2011 defect notification, MB stated that to remediate the potential need for excessive brake force it would conduct a safety recall (11V-208) to replace the switch with a more robustly designed component.The recall includes 136,751 model year 2000 - 2002 M-Class and model year 2000 - 2004 M-Class AMG vehicles.Owner notification letters will be mailed
Vehicle Speed Control:cruise Control
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 evaluation of field return failures.MB identified both 1) electrical contact and 2) mechanical switch failure mechanisms.According to MB's analysis, electrical contact failure is the predominate failure type and the failure consequence depends on which contact fails.For instance MB claims that BLS contact failures are momentary in nature and do not affect brake light operation but are nonetheless detected by the OBD system, resulting in a DTC and subsequent replacement.Electrical contact failures of the BS and EWM contacts result in a DTC also, and EWM contact failures result in the shifter being stuck in the park (which can be overridden by the consumer).Accordingly MB maintains that electrical contact failures of the switch have no safety consequence since the brake lamps remain operational and the cruise control is always disabled.MB determined that mechanical failures of the switch, which are rare in their assessment, can result from internal wear and/or increased switch operating temperatures.High temperatures occur due to overheating of the BLS contacts and can cause the internal plastic components to melt.In one scenario overheated BLS contacts may melt to the extended plunger and are damaged when the brake pedal is released resulting in the brake lights staying on.In another scenario the increased temperatures and/or internal wear can cause the plunger to stick in the fully depressed position.In this case the cruise may not cancel when the brake is applied and the driver may have to use high brake pedal forces or other means (shifting to neutral or using the cruise master switch) to disengage the cruise.Additionally the vacuum assist can be depleted if the driver pumps the brakes resulting in reduced braking effectiveness and even higher pedal forces.In its March 31, 2011 defect notification, MB stated that to remediate the potential need for excessive brake force it would conduct a safety recall (11V-208) to replace the switch with a more robustly designed component.The recall includes 136,751 model year 2000 - 2002 M-Class and model year 2000 - 2004 M-Class AMG vehicles.Owner notification letters will be mailed
Vehicle Speed Control
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 evaluation of field return failures.MB identified both 1) electrical contact and 2) mechanical switch failure mechanisms.According to MB's analysis, electrical contact failure is the predominate failure type and the failure consequence depends on which contact fails.For instance MB claims that BLS contact failures are momentary in nature and do not affect brake light operation but are nonetheless detected by the OBD system, resulting in a DTC and subsequent replacement.Electrical contact failures of the BS and EWM contacts result in a DTC also, and EWM contact failures result in the shifter being stuck in the park (which can be overridden by the consumer).Accordingly MB maintains that electrical contact failures of the switch have no safety consequence since the brake lamps remain operational and the cruise control is always disabled.MB determined that mechanical failures of the switch, which are rare in their assessment, can result from internal wear and/or increased switch operating temperatures.High temperatures occur due to overheating of the BLS contacts and can cause the internal plastic components to melt.In one scenario overheated BLS contacts may melt to the extended plunger and are damaged when the brake pedal is released resulting in the brake lights staying on.In another scenario the increased temperatures and/or internal wear can cause the plunger to stick in the fully depressed position.In this case the cruise may not cancel when the brake is applied and the driver may have to use high brake pedal forces or other means (shifting to neutral or using the cruise master switch) to disengage the cruise.Additionally the vacuum assist can be depleted if the driver pumps the brakes resulting in reduced braking effectiveness and even higher pedal forces.In its March 31, 2011 defect notification, MB stated that to remediate the potential need for excessive brake force it would conduct a safety recall (11V-208) to replace the switch with a more robustly designed component.The recall includes 136,751 model year 2000 - 2002 M-Class and model year 2000 - 2004 M-Class AMG vehicles.Owner notification letters will be mailed
PE07007 · Electronic Stability Control Malfunction
Opened Feb 1, 2007 · Closed Jul 11, 2007
Status: closed (inferred from source dates) · Electronic Stability Control:automatic (asc)
ODI OPENED PE07-007 AFTER RECEIVING 4 COMPLAINTS WITHIN A 6 WEEK PERIOD ALLEGING INCIDENTS OF UNCOMMANDED BRAKE APPLICATION IN MODEL YEAR (MY) 2000 THROUGH 2001 MERCEDES M CLASS SPORT UTILITY VEHICLES.INFORMATION CONTAINED IN THE REPORTS OR GATHERED IN SUBSEQUENT CONSUMER INTERVIEWS INDICATED THAT THE INCIDENTS WERE CAUSED BY FAULTS IN THE ELECTRONIC STABILITY PROGRAM (ESP) SYSTEM WHICH WERE REPAIRED BY REPLACING THE YAW RATE SENSORS.ALTHOUGH THE SAME YAW RATE SENSOR IS USED IN APPROXIMATELY 800,000 OTHER MERCEDES M-CLASS, C-CLASS AND SLK MODELS, TO DATE THERE HAS BEEN ONLY ONE RELATED COMPLAINT TO ODI IN THOSE VEHICLES. DURING THIS INVESTIGATION MERCEDES BENZ PROVIDED ODI WITH 327 COMPLAINTS RELATED TO THE ESP SYSTEM IN THE MY 2000 THROUGH 2001 M CLASS VEHICLES.SEVEN OF THE COMPLAINTS SUBMITTED BY MERCEDES ALLEGED INCIDENTS OF UNCOMMANDED BRAKE ACTIVATION WHILE DRIVING, WITH TWO OF THESE INVOLVING VEHICLES IDENTIFIED IN THE ODI COMPLAINTS.NONE OF THE INCIDENTS RESULTED IN CRASH OR INJURY.HOWEVER, THE OWNERS DID EXPRESS SAFETY CONCERNS DUE TO THE SUDDEN, UNEXPECTED CHANGE IN VEHICLE SPEED AND DIRECTION. ON MAY 10, 2007 MERCEDES BENZ MET WITH NHTSA TO PROVIDE A TECHNICAL PRESENTATION AND CONDUCT A DRIVING DEMONSTRATION OF THE ESP SYSTEM PERFORMANCE WITH SIMULATED ELECTRICAL FAULTS IN THE YAW RATE SENSOR.MERCEDES SHOWED THAT THE ESP SYSTEM IS PROGRAMMED TO DIAGNOSE ELECTRICAL FAULTS AND THAT BRAKE APPLICATIONS RESULTING FROM YAW RATE SENSOR ELECTRICAL FAULTS ARE VERY SHORT IN DURATION (0.3 SECONDS OR LESS) AND DO NOT AFFECT VEHICLE CONTROL OR STABILITY. NINE OF THE CONSUMER COMPLAINTS TO ODI AND MERCEDES ALLEGED BRAKE ACTIVATIONS LONGER THAN 0.3 SECONDS, WITH SEVERAL ALLEGING THAT THE INCIDENT LASTED UNTIL THE VEHICLE CAME TO A STOP.A COMPLAINT VEHICLE THAT ALLEGED MULTIPLE INCIDENTS WAS EVALUATED BY ODI AT THE VEHICLE RESEARCH AND TEST CENTER (VRTC) IN EAST LIBERTY, OHIO.VRTC WAS UNABLE TO DUPLICATE THE CONDITION.DUE TO THE LOW COMPLAINT RATE AND ONLY ONE NEW COMPLAINT TO ODI OR MERCEDES SINCE JANUARY 2007, THIS INVESTIGATION HAS BEEN CLOSED.ODI WILL CONTINUE TO MONITOR COMPLAINTS IN THE SUBJECT VEHICLES AND OTHER MERCEDES PRODUCTS USING THE SAME YAW RATE SENSOR AND MERCEDES WILL PROVIDE UPDATES ON FIELD EXPERIENCE (COMPLAINTS, FIELD REPORTS AND WARRANTY CLAIMS) THROUGH THE END OF 2007.
PE03006 · Power Steering Hose Assembly Leakage
Opened Feb 13, 2003 · Closed Apr 4, 2003
Status: closed (inferred from source dates) · Steering:hydraulic Power Assist:hose, Piping, And Connections; Steering:hydraulic Power Assist:power Steering Fluid
THE HOSE CLAMP USED TO SECURE THE POWER STEERING FLUID COOLING HOSE TO THE STEERING FLUID COOLER MAY NOT PROVIDE SUFFICIENT CLAMPING FORCE FOR THE CONNECTION.THE LOSS OF POWER STEERING FLUID MAY RESULT IN GRADUAL REDUCTION IN POWER STEERING ASSIST (I.E., INCREASED STEERING EFFORT) OVER TIME, WITH POTENTIAL DAMAGE TO THE POWER STEERING PUMP. THERE HAVE ALSO BEEN A FEW INCIDENTS OF HOSE SEPARATION FROM THE FITTING, THAT HAVE RESULTED IN MORE RAPID REDUCTIONS OF POWER STEERING.TESTING CONDUCTED BY MERCEDES-BENZ INDICATES THAT THE LEAKED FLUID IS NOT LIKELY TO BE EXPOSED TO HOT ENGINE COMPONENTS.THERE ARE NO KNOWN ALLEGATIONS THAT THE DEFECT CONDITION HAS CAUSED A VEHICLE FIRE. MERCEDES-BENZ WILL CONDUCT A VOLUNTARY RECALL CAMPAIGN FOR THE SUBJECT M-CLASS VEHICLES.MERCEDES-BENZ WILL INSTALL A NEW HOSE CLAMP ON THE POWER STEERING HOSE TO THE POWER STEERING COOLER OF THE SUBJECT VEHICLES.DURING CLAMP REPLACEMENT, THE POWER STEERING COOLING HOSE WILL BE INSPECTED AND REPLACED AS NECESSARY.
Additional source detail variants (2)
Steering:hydraulic Power Assist:hose, Piping, And Connections
THE HOSE CLAMP USED TO SECURE THE POWER STEERING FLUID COOLING HOSE TO THE STEERING FLUID COOLER MAY NOT PROVIDE SUFFICIENT CLAMPING FORCE FOR THE CONNECTION.THE LOSS OF POWER STEERING FLUID MAY RESULT IN GRADUAL REDUCTION IN POWER STEERING ASSIST (I.E., INCREASED STEERING EFFORT) OVER TIME, WITH POTENTIAL DAMAGE TO THE POWER STEERING PUMP. THERE HAVE ALSO BEEN A FEW INCIDENTS OF HOSE SEPARATION FROM THE FITTING, THAT HAVE RESULTED IN MORE RAPID REDUCTIONS OF POWER STEERING.TESTING CONDUCTED BY MERCEDES-BENZ INDICATES THAT THE LEAKED FLUID IS NOT LIKELY TO BE EXPOSED TO HOT ENGINE COMPONENTS.THERE ARE NO KNOWN ALLEGATIONS THAT THE DEFECT CONDITION HAS CAUSED A VEHICLE FIRE. MERCEDES-BENZ WILL CONDUCT A VOLUNTARY RECALL CAMPAIGN FOR THE SUBJECT M-CLASS VEHICLES.MERCEDES-BENZ WILL INSTALL A NEW HOSE CLAMP ON THE POWER STEERING HOSE TO THE POWER STEERING COOLER OF THE SUBJECT VEHICLES.DURING CLAMP REPLACEMENT, THE POWER STEERING COOLING HOSE WILL BE INSPECTED AND REPLACED AS NECESSARY.
Steering:hydraulic Power Assist:power Steering Fluid
THE HOSE CLAMP USED TO SECURE THE POWER STEERING FLUID COOLING HOSE TO THE STEERING FLUID COOLER MAY NOT PROVIDE SUFFICIENT CLAMPING FORCE FOR THE CONNECTION.THE LOSS OF POWER STEERING FLUID MAY RESULT IN GRADUAL REDUCTION IN POWER STEERING ASSIST (I.E., INCREASED STEERING EFFORT) OVER TIME, WITH POTENTIAL DAMAGE TO THE POWER STEERING PUMP. THERE HAVE ALSO BEEN A FEW INCIDENTS OF HOSE SEPARATION FROM THE FITTING, THAT HAVE RESULTED IN MORE RAPID REDUCTIONS OF POWER STEERING.TESTING CONDUCTED BY MERCEDES-BENZ INDICATES THAT THE LEAKED FLUID IS NOT LIKELY TO BE EXPOSED TO HOT ENGINE COMPONENTS.THERE ARE NO KNOWN ALLEGATIONS THAT THE DEFECT CONDITION HAS CAUSED A VEHICLE FIRE. MERCEDES-BENZ WILL CONDUCT A VOLUNTARY RECALL CAMPAIGN FOR THE SUBJECT M-CLASS VEHICLES.MERCEDES-BENZ WILL INSTALL A NEW HOSE CLAMP ON THE POWER STEERING HOSE TO THE POWER STEERING COOLER OF THE SUBJECT VEHICLES.DURING CLAMP REPLACEMENT, THE POWER STEERING COOLING HOSE WILL BE INSPECTED AND REPLACED AS NECESSARY.