IllustrationSTEERING IS HARD TO TURN. OVER HEATS AND WILL NOT KEEP COOLINAT DOWN
2000 Mercedes Benz ML320
Owner reports · Recalls · Investigations
More warning signs than most ML320 years
Owner complaints for the 2000 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
90–25K
2025–50K
2250–75K
1775–100K
20100–150K
19150K+
107 reports with mileage · 59 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.
- Steering. Review the 45 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Engine And Engine Cooling. Review the 27 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Electrical System. Review the 20 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
NHTSA owner reports · September 18, 2026 snapshot.
13 crash reports6 fire reports13 injury reports
Vehicle Speed Control complaints
9 reportsWAS DRIVING TRUCK AT HIGHWAY, WHEN BRAKES ACTIVATED BY ITSELF, ABS, TRACTION LIGHT, BRAKE LAMP AND HAZARDS FLASHED. HAD TO IMMEDIATELY MOVE TO SIDE OF ROAD, WHILE BRAKES WHERE ACTIVATING. FELT AS IF ABS WAS ACTIVATING AS IF I WAS SLIDING ON AND ICY ROAD. HAD TO HAVE VEHICLE TOWED AS I WAS NOT ABLE TO MOVE MORE THAT 5 FEET
I WAS ON THE FREEWAY, I WAS USING MY CRUISE CONTROL (LUCKILY JUST AFTER HEAVY TRAFFIC HOURS) JUST LIKE ANY OTHER DAY. A CAR SLOWED IN FRONT OF ME, SO I WENT TO APPLY MY BRAKES. AS SOON AS I HIT THE BRAKE PEDAL THE BRAKES NOT ONLY DID NOT DISENGAGE THE CRUISE CONTROL BUT THE BRAKES GOT STIFF AND WOULD NOT WORK NO MATTER HOW HARD …
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I WAS ON THE FREEWAY, I WAS USING MY CRUISE CONTROL (LUCKILY JUST AFTER HEAVY TRAFFIC HOURS) JUST LIKE ANY OTHER DAY. A CAR SLOWED IN FRONT OF ME, SO I WENT TO APPLY MY BRAKES. AS SOON AS I HIT THE BRAKE PEDAL THE BRAKES NOT ONLY DID NOT DISENGAGE THE CRUISE CONTROL BUT THE BRAKES GOT STIFF AND WOULD NOT WORK NO MATTER HOW HARD I PRESSED THEM. AT THE SAME TIME THE ACCELERATOR WAS FLOORED AND THE CAR WAS TRYING TO GO WHAT SEEMS LIKE 130-140 MPH. IT TOOK ALL MY STRENGTH TO TRY AND KEEP IT AT AN APPROPRIATE SPEED. LUCKILY MY PASSENGER TOLD ME TO STAY CALM AND TRIED TO HELP ME DISENGAGE THE CRUISE CONTROL. I HAD TO MANEUVER THE CAR TO THE SLOWEST LANE AND SHIFT IT INTO NEUTRAL. THAT WAS THE ONLY OPTION I HAD BESIDES CRASHING INTO THE CAR IN FRONT OF ME. I AM EXTREMELY SHAKEN FROM THIS EVENT, I HAVE ANXIETY/PANIC ATTACKS WHENEVER I DRIVE ANY VEHICLE NOW. I AM CURRENTLY LOOKING FOR A PHYSICIAN TO HELP ME WORK OUT SOME KIND OF TREATMENT/THERAPY.
WHILE DRIVING AROUND 50MPH ON THE BQE ROAD (NY), SUDDENLY THE BAS/ESP LIGHT CAME ON, ALL THE BRAKES ENGAGED AND CAR WAS COMING TO A STOP. WARNING LIGHT ON A DASHBOARD WAS FLASHING AND AT FIRST I THOUGHT THE ENGINE DIED. *TR NOT REALIZING WHAT IS HAPPENING, I TRIED TO ADD POWER/GAS TO THE CAR, BUT THE ENGINE DIDN'T WANT TO GO P…
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WHILE DRIVING AROUND 50MPH ON THE BQE ROAD (NY), SUDDENLY THE BAS/ESP LIGHT CAME ON, ALL THE BRAKES ENGAGED AND CAR WAS COMING TO A STOP. WARNING LIGHT ON A DASHBOARD WAS FLASHING AND AT FIRST I THOUGHT THE ENGINE DIED. *TR NOT REALIZING WHAT IS HAPPENING, I TRIED TO ADD POWER/GAS TO THE CAR, BUT THE ENGINE DIDN'T WANT TO GO PAST 1000 RPM. BEING IN A FAST LANE AND HAVING HARD TIME CONTROLLING THE MOVEMENT OF THE CAR, I??VE NOTICED OVERPOWERING SMELL OF THE BRAKES. I WAS ABSOLUTELY SHOCKED BY THE EVENT AS THE TRAFFIC WAS HEAVY AND I WAS JUST HOPING NO ONE WILL REAR ME. STEPPING ON THE GAS PEDAL HAD ALMOST NO RESULT EVEN THOUGH THE MOTOR WAS RUNNING. IT THEN STARTED TO ACCELERATE VERY SLOWLY WHEN MY FOOT WAS PRESSING THE GAS PEDAL ALL THE WAY TO THE FLOOR OF THE CAR. SOME 5-10 MINUTES LATER, THE CAR STARTED TO ACCELERATE AND BEHAVING AS NOTHING HAS HAPPENED. HOWEVER, 15 MINUTES INTO THE RIDE, THE SAME THING HAPPENED AND THIS TIME, I WAS DRIVING IN A SLOW LANE - SOME 30-35 MPH. I PULLED OVER AND LET THE CAR REST FOR ABOUT 5 MINUTES AND IT STARED FINE AND DROVE FINE FOR THE REST OF THE EVENING. ONCE I PARKED THE CAR, THE BAS ESP LIGHT WAS STILL ON AND STAYED ON. I TOOK THE CAR VERY NEXT DAY TO A CAR MECHANIC, BUT THE COMPUTER READING DIDN??T GIVE ANY ERRORS, FAULTS NOR NOTIFICATIONS. BY THAT TIME, THE ESP LIGHT WAS OFF ONCE AGAIN. THE INCIDENT RECURRED 3 DAYS LATER WHILE COMING TO A STOP DUE TO A TRAFFIC LIGHTS - SOME 15-20 MPH. MY MECHANIC (AND MY INTERNET SEARCH) ADVISED ME TO CHANGE THE YAW SENSOR. I FULLY UNDERSTAND THE SENSOR CAN BECOME FAULTY, BUT FULLY ENGAGING THE BRAKES WHILE TRAVELING IS EXTREMELY DANGEROUS. I'M NOW WAITING FOR THE YAW SENSOR TO BE REPLACED. *TR
I AM THE OWNER IF A 2000 MERCEDES ML320. THIS MORNING AS I CAME HOME ON THIS CAR AND SUDDENLY IT SPED UP AND LOST CONTROL WHEN IT CAME TO THE DRIVEWAY. I LEG WAS ON THE BRAKE WHEN I CAME TO THE DRIVEWAY NO WAY I COULD HAVE PUT MY LEG ON THE ACCELERATOR. I BELIEVE THERE IS A DEFECT IN ITS DESIGN AND CAUSE IT TO SUDDENLY SPEED UP.…
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I AM THE OWNER IF A 2000 MERCEDES ML320. THIS MORNING AS I CAME HOME ON THIS CAR AND SUDDENLY IT SPED UP AND LOST CONTROL WHEN IT CAME TO THE DRIVEWAY. I LEG WAS ON THE BRAKE WHEN I CAME TO THE DRIVEWAY NO WAY I COULD HAVE PUT MY LEG ON THE ACCELERATOR. I BELIEVE THERE IS A DEFECT IN ITS DESIGN AND CAUSE IT TO SUDDENLY SPEED UP. PLEASE LOOK INTO THIS SINCE IT CAN BE A SERIOUS MATTER. MY OTHER 2 CARS IN THE GARAGE WERE BADLY DAMAGED IN ADDITION TO THE THIS ML320.*TR
I WAS DRIVING UP HILL IN SLOW TRAFFIC FOR ABOUT 5 TO 10 MILES PER HOUR FOR A FEW MILES THEN ALL THE SUDDEN LEARNED CAR DID NOT RESPOND TO THE GAS PEDAL I PUT PRESSURE ON. THE CAR JERK A LITTLE BID AND WON'T MOVE MUCH ONLY BY THE INCHES. THEN I HAD TO PULL OFF THE ROAD. I TURNED OFF THE ENGINE AND WAITED FOR FEW MINUTES AND STAR…
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I WAS DRIVING UP HILL IN SLOW TRAFFIC FOR ABOUT 5 TO 10 MILES PER HOUR FOR A FEW MILES THEN ALL THE SUDDEN LEARNED CAR DID NOT RESPOND TO THE GAS PEDAL I PUT PRESSURE ON. THE CAR JERK A LITTLE BID AND WON'T MOVE MUCH ONLY BY THE INCHES. THEN I HAD TO PULL OFF THE ROAD. I TURNED OFF THE ENGINE AND WAITED FOR FEW MINUTES AND STARTED AGAIN, TURNED AROUND AND CANCELLED MY TRIP. A SIMILAR INSTANCE HAPPENED ONCE BEFORE SEVERAL YEARS AGO. I TOOK THE CAR TO THE DEALER AND THEY FOUND NOTHING WRONG. *TR
DT: CALLER HAS HAD VEHICLE IN 6 TIMES FOR CHECK ENGINE LIGHT/SPARK PLUGS BEING CORRODED/LOOSE WHEEL BEARING/CONTROL MODULE WENT OUT/FOR SHAKING AND SPUTTERING AT IDLE, AND THE ELECTRIC FUNCTION CHECK. MANUFACTURER HAS NOT BEEN CONTACTED YET. *AK
VEHICLE ENGAGED FROM PARK TO DRIVE, AND THEN INTO REVERSE AND ACCELERATED AND CRASHED INTO A TREE. THE DEALER WAS NOTIFIED, AND STATED IT WAS A HUMAN ERROR. *AK THE VEHICLE WAS IN PARK, THEN PLACED IN REVERSE, BACKED UP A COUPLE OF FEET, AND THEN THE CONSUMER PLACED THE VEHICLE IN DRIVE TO GO FORWARD TO STRAIGHTEN OUT IN O…
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VEHICLE ENGAGED FROM PARK TO DRIVE, AND THEN INTO REVERSE AND ACCELERATED AND CRASHED INTO A TREE. THE DEALER WAS NOTIFIED, AND STATED IT WAS A HUMAN ERROR. *AK THE VEHICLE WAS IN PARK, THEN PLACED IN REVERSE, BACKED UP A COUPLE OF FEET, AND THEN THE CONSUMER PLACED THE VEHICLE IN DRIVE TO GO FORWARD TO STRAIGHTEN OUT IN ORDER TO BACK OUT OF THE DRIVEWAY MORE EASILY. THE VEHICLE HAD GONE INTO REVERSE, ACCELERATED AT A TREMENDOUS SPEED AND HAD GONE DOWN THE DRIVEWAY OUT OF CONTROL, VEERED RIGHT ONTO THE LAWN AND HIT THE TREE. THE GEAR SHIFT WAS STILL IN DRIVE WHEN THE VEHICLE STOPPED ON IMPACT. *SCC *JB
MERCEDES MODEL ML320 WAS PARKED IN DRIVEWAY; UPON SWITCHING TO REVERSE, SUDDEN UNITENTIONAL ACCELERATION RAFTER SUA, DRIVER UNABLE TO CONTROL VEHICLE; CRASHED REAR OF CAR INTO TREE ACROSS THE STREET.*AK
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
4PE10050 · 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.
PE03058 · Engine Crankshaft Pulley Failure
Opened Dec 17, 2003 · Closed Apr 22, 2004
Status: closed (inferred from source dates) · Engine And Engine Cooling:engine:gasoline:belts And Associated Pulleys
THE OFFICE OF DEFECTS INVESTIGATION (ODI) OPENED THIS PRELIMINARY EVALUATION TO INVESTIGATE ALLEGATIONS OF ENGINE CRANKSHAFT PULLEY HARMONIC BALANCER FAILURE THAT COULD RESULT IN LOSS OF POWER-STEERING ASSIST.ODI HAS RECEIVED A TOTAL OF 546 NON-DUPLICATIVE REPORTS THAT ALLEGE ENGINE CRANKSHAFT PULLEY HARMONIC BALANCER FAILURE ON ALL MERCEDES-BENZ VEHICLES USING THE SUBJECT COMPONENT.THE SUBJECT COMPONENT FAILURES ARE PROGRESSIVE IN NATURE AND ONLY A SMALL PERCENTAGE OF THE COMPLAINTS AND WARRANT CLAIMS INVOLVED A FAILURE THAT HAD PROGRESSED FAR ENOUGH TO EFFECT POWER STEERING PERFORMANCE (6 OF 55 ODI COMPLAINTS REFERENCE INCREASED STEERING EFFORT).THERE HAVE BEEN NO CRASHES OR INJURIES RELATED TO THE ALLEGED DEFECT.A SAFETY-RELATED DEFECT HAS NOT BEEN IDENTIFIED AT THIS TIME AND FURTHER USE OF AGENCY RESOURCES DOES NOT APPEAR TO BE WARRANTED.ACCORDINGLY, THIS INVESTIGATION IS CLOSED.THE CLOSING OF THIS INVESTIGATION DOES NOT CONSTITUTE A FINDING BY NHTSA THAT A SAFETY-RELATED DEFECT DOES NOT EXIST.THE AGENCY WILL TAKE FURTHER ACTION IF WARRANTED BY THE CIRCUMSTANCES.SEE SUMMARY REPORT ATTACHED FOR FURTHER DETAIL.
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.