Investigations
| NHTSA ID | Manufacturer | Date open | Date close | Subject | Recall campaign | |
|---|---|---|---|---|---|---|
| VEHICLE SPEED CONTROL | ||||||
| PE10050 | MERCEDES-BENZ USA, LLC. | 12/21/2010 | 05/04/2011 | Brake lamp switch failure. | 11V208000 | |
| 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 to consumers in september 2011.this action taken by mb is sufficient to resolve the issues raised by this investigation. | ||||||
| VEHICLE SPEED CONTROL - CRUISE CONTROL | ||||||
| PE10050 | MERCEDES-BENZ USA, LLC. | 12/21/2010 | 05/04/2011 | Brake lamp switch failure. | 11V208000 | |
| 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 to consumers in september 2011.this action taken by mb is sufficient to resolve the issues raised by this investigation. | ||||||
Consumer Complaints
| Fail date | miles | occurences | Purchase date |
|---|---|---|---|
| VEHICLE SPEED CONTROL | |||
| 03/13/2009 | 83367 | ||
| Tl - the contact owns a 2002 mercedes benz ml320. the contact stated that while driving with the cruise control the vehicle suddenly accelerated up to 90 mph. the contact mentioned that she was unable to disengaged the cruise control although she was depressing the break pedal. the vehicle was taken to the dealer who diagnosed that the accelerator cruise control, and the electric kit were defective and needed to be replaced. the manufacturer was not made aware of the failure. the vehicle was repaired. the failure mileage was 83,367 and the current mileage was 113,000. pm | |||
| 12/18/2009 | 112000 | ||
| To whom it may concern, i had a near death experience while driving one of your vehicles. i am the owner of a mercedes 2002 ml320, which was purchased at a phillips mercedes dealership in virginia beach va. i need to address a very serious incident that occurred over the weekend (december 18, 2010). i was driving back from richmond going toward virginia beach, i was driving 70 mph on i-64 and had it on cruise control, ahead i saw that traffic slowing down so i stepped on the break; i then realized that my breaks weren | |||
| 06/19/2010 | 88000 | ||
| Tl- the contact owns a 2002 mercedes ml320. the contact states while on the freeway going approximately 60mph, all of a sudden the vehicle felt different and the vehicle accelerated without driver intent up about 70mph. the owner stepped on the brake but the vehicle didn't slow down. she put both feet on the brake and it slowed down about 5mph. she pulled the emergency brake and put it in neutral and the vehicle slowed down and was able to get it to the side of the road. the vehicle was towed to a mercedes dealer and they stated they were going to do diagnostics. the vehicle is still at the dealer and has not been repaired yet. the failure and current mileage is approximately 88,000. rd | |||
| 05/13/2010 | 118206 | ||
| [mercedes benz ml 320 2002] while driving east on route 80 at 65 mph and approaching the toll booths of the george washington bridge, i tapped my brakes to disengage my speed control. the speed control did not shut down. i hit the brake pedal several more times harder and harder, but the speed control stayed in control. i pushed down very hard on the brake pedal with both feet and although the car slowed a little, the speed control dramatically speeded up the engine with the tachometer going almost full scale. i was able to reduce the car's speed from about 65 to under 50 mph, but was still pretty scared. this was a terrifying experience and as an engineer i realized my options and time to react were very limited! i figured my choices were few: 1) brake until the car either stopped or i had hit the stopped cars at the toll booths (maybe damage the trasmission further), 2) shift the car into neutral hoping that either the speed control would disengage or at least i could stop the car (engine rpms might run away and destroy the engine), or 3) try to shut off the speed control with the control stalk on the left of the steering column (which i obviously could not read closely to figure out where the stop might be). fortunately, with several tries i was able to find the stop position on the speed control stalk and disenegage the control. i braked very hard to stop short of a collision..... and got harsh words and looks from the adjacent toll collectors. i suspected that the brake light switch was not working and this was confirmed by my mechanic (eddie rodriguez of eddy's total auto care). the mechanic also has to replace the brake pressure sensor. my wife is insisting that i get ridof the car immediately and buy a new car. i love my ml 320..... but i love my wife too! | |||
| 10/30/2008 | 105003 | 1 | |
| Was driving vehicle on highway at 75 mph set speed in cruise control and stepped on brake as i approached traffic congestion. vehicle would not stop and continued to maintain set speed regardless how hard i pressed on the brake. eventually, i decided to try shifting into neutral and the vehicle was placed back under control of the footbrake. thankfully, the vehicle was slowed down without incident but it was a very scary moment. noticed, at this time, the bas/esp malfunction indicator lamp was displayed on the dashboard. drove vehicle directly to a mercedes dealership for repairs. dealer advised stop lamp switch shorted. replaced lamp switch. although, this was the first incident while in cruise control the vehicle did have similar past problems with the braking system (ie-brake switch and shifter control module were replaced) that prevented shifting out of park into any other position. vehicle should have safety device to override cruise control or prevent cruise control operation with any malfunction in the braking system or activation of the braking indicator lamp. what assurances are there to prevent this from happening again? *tr | |||
| 09/08/2006 | 35000 | 1 | 10/11/2001 |
| Mb ml 320 continued to accelerate while exiting a parking ramp while not touching the accelerator and with braking having no effect on reducing speed until car impacted wall. *jb | |||
| VEHICLE SPEED CONTROL - CRUISE CONTROL | |||
| 06/11/2007 | 102000 | 1 | 08/01/2001 |
| Driving on rt 30 in camden nj when my vehicle began accelerating at high rate of speed (i was traveling at 50mph and vehicle sped up to about 80 and i could not stop it). i had to put emergency brakes and ultimately put vehicle into park to get it to stop. nothing in vehicle caused vehicle to accelerate and vehicle did not stop and nearly caused me to drive into traffic. mercedes denies having any problems with vehicles and blamed me for operation. i have been driving on the road as a police officer for 14 years and know that it was an issue with vehicle that caused this problem | |||