Emergency Braking System Malfunctions
Junior Member
Joined: Feb 2023
Posts: 30
Likes: 1
C300 4Matic, DX1 Trim, AMG line, Panoramic roof, Black paint with grey interior
You may want to try adjusting sensitivities to minimum levels. I’ve not experienced the “full brake for no reason” since, but it sure beeps as though I’m an inch from disaster…. My dealership said that it was a common complaint but no response from MB.. Sure agree that MB owes us all a fix!
Out Of Control!!
Joined: Apr 2019
Posts: 12,058
Likes: 6,848
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
super simple fix
You may want to try adjusting sensitivities to minimum levels. I’ve not experienced the “full brake for no reason” since, but it sure beeps as though I’m an inch from disaster….
My dealership said that it was a common complaint but no response from MB.. Sure agree that MB owes us all a fix!
My dealership said that it was a common complaint but no response from MB.. Sure agree that MB owes us all a fix!
This issue can be easily mitigated with STABLE VOLTAGE.
The chassis uses Bosch variable voltage BUT IS NOT COMPLIANT with variable power supply.
The unstable voltage cause modules to downgrade bandwidth speeds of CAN networks.
You can experimentally unplug ALT LIN under 5mn to find out the WHOLE CHASSIS RUNS BETTER including :
- the laggy/precise engine throttle
- tranny sloppy/perfect shifts
- the ESP brakes "limited..." faults
- the ghost/sensitive radars
- unstable CAN-Bus networking
Rebooting chassis will restart voltage adaptations by CAN Modules.
Once you're done dealing with unstable voltage, you can look into "oil pump solenoid" limiting pressure under 3500.Rpm...
Last edited by CaliBenzDriver; Jan 5, 2025 at 12:52 PM.
Junior Member
Joined: Jul 2024
Posts: 73
Likes: 14
2015 mercedes benz e400 4matic
Hi All
I am the owner of a 2018 e400 wagon. My vehicle has persistent "false alarm" activation of the radar-driven safety systems, including the emergency braking system.
I'm in communication with MBUSA on these issues. Their position is that the system is "operating as designed" and they are refusing to take action. They are also telling me that mine is an isolated incident, which I know to be untrue from other forum members sharing their same issues.
What I'd like to try to do is get more visibility into how much this is occurring. I've seen at least 3 other members with the same issue just in the E-class forums, and a few scattered around other models. Maybe if we get a large enough group together, who are all experiencing these issues, we can get MBUSA to step up and do the right thing - before someone gets seriously injured, or worse, by these issues.
So if you are experiencing these issues - false alarms, sudden braking, the system killing the accelerator because it thinks there's an obstacle - please post below, and we will try to get some more attention focused on this serious issue.
Current list of members (as of Aug 28) who have experienced this issue and cited it in either this thread or another:
1. Me, e400 wagon
2. Sunrose 305, e300
3. Brittnie jane, C300
4. Diesel Dan, e550
5. RSnovi, glk250
6. DDgator, glc
7. Bert.DS glc350e
8. Senatov
9. Frandumont glc300 (dirty sensors?)
10. Mickhoog
11. The_Judge e400 coupe
12. sackboydad, e450 cab
13. Streamliner, s560
14. Absent, s560 (loaner)
15. Malmokalle, e class
16. MBZ2019, a class
17. Legume, e400 wagon
18. Darren Boey, C350e
19. Utsenmo, C300
I am the owner of a 2018 e400 wagon. My vehicle has persistent "false alarm" activation of the radar-driven safety systems, including the emergency braking system.
I'm in communication with MBUSA on these issues. Their position is that the system is "operating as designed" and they are refusing to take action. They are also telling me that mine is an isolated incident, which I know to be untrue from other forum members sharing their same issues.
What I'd like to try to do is get more visibility into how much this is occurring. I've seen at least 3 other members with the same issue just in the E-class forums, and a few scattered around other models. Maybe if we get a large enough group together, who are all experiencing these issues, we can get MBUSA to step up and do the right thing - before someone gets seriously injured, or worse, by these issues.
So if you are experiencing these issues - false alarms, sudden braking, the system killing the accelerator because it thinks there's an obstacle - please post below, and we will try to get some more attention focused on this serious issue.
Current list of members (as of Aug 28) who have experienced this issue and cited it in either this thread or another:
1. Me, e400 wagon
2. Sunrose 305, e300
3. Brittnie jane, C300
4. Diesel Dan, e550
5. RSnovi, glk250
6. DDgator, glc
7. Bert.DS glc350e
8. Senatov
9. Frandumont glc300 (dirty sensors?)
10. Mickhoog
11. The_Judge e400 coupe
12. sackboydad, e450 cab
13. Streamliner, s560
14. Absent, s560 (loaner)
15. Malmokalle, e class
16. MBZ2019, a class
17. Legume, e400 wagon
18. Darren Boey, C350e
19. Utsenmo, C300
Joined: Nov 2016
Posts: 7,847
Likes: 3,498
From: Maryland
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Joined: Nov 2016
Posts: 7,847
Likes: 3,498
From: Maryland
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
This issue here is that the Collision Avoidance (or some other feature) causes the brakes to be applied fully and automatically while driving.
I can see something like this quickly deteriorating into a bad situation... Randy in his monster truck is following too closely. The prissy Mercedes S-Class (which costs ALMOST as much as Randy's Dodge MegaRam) in front of him is going too slow for Randy's likings. Suddenly the Mercedes slams on it's brakes and genius Monster Truck Randy assumes it was on purpose. What follows is not pretty.
I can see something like this quickly deteriorating into a bad situation... Randy in his monster truck is following too closely. The prissy Mercedes S-Class (which costs ALMOST as much as Randy's Dodge MegaRam) in front of him is going too slow for Randy's likings. Suddenly the Mercedes slams on it's brakes and genius Monster Truck Randy assumes it was on purpose. What follows is not pretty.
Joined: Nov 2016
Posts: 7,847
Likes: 3,498
From: Maryland
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
I have read through this thread before as I have had this issue happen multiple times. I assumed sensors were dirty or rain was causing confusion with the system and have not raised with the dealership as of yet. The first time I was driving down a suburban road, a pedestrian was about 100 yards ahead, nothing nearby and the car brakes slammed on. It happened again on my neighborhood street which is a very quiet street going about 15 MPH. The alarm sometimes beeps when going around the rotary near my house where there is a curb close by.
Today it just happened again on a busy shopping district street in Boston with lots of pedestrian traffic, I was waiting at the light and started to turn right after pedestrians crossed, only to have brakes slammed on causing me to lurch forward. I was so scared I did hit something, only to find out there was nothing to cause this. I am terrified of this car and after this incident want to get rid of it.
Nightmare!!
Today it just happened again on a busy shopping district street in Boston with lots of pedestrian traffic, I was waiting at the light and started to turn right after pedestrians crossed, only to have brakes slammed on causing me to lurch forward. I was so scared I did hit something, only to find out there was nothing to cause this. I am terrified of this car and after this incident want to get rid of it.
Nightmare!!
Newbie
Joined: Feb 2015
Posts: 1
Likes: 1
From: Palm Springs
2020 E350
Hi All
I am the owner of a 2018 e400 wagon. My vehicle has persistent "false alarm" activation of the radar-driven safety systems, including the emergency braking system.
I'm in communication with MBUSA on these issues. Their position is that the system is "operating as designed" and they are refusing to take action. They are also telling me that mine is an isolated incident, which I know to be untrue from other forum members sharing their same issues.
What I'd like to try to do is get more visibility into how much this is occurring. I've seen at least 3 other members with the same issue just in the E-class forums, and a few scattered around other models. Maybe if we get a large enough group together, who are all experiencing these issues, we can get MBUSA to step up and do the right thing - before someone gets seriously injured, or worse, by these issues.
So if you are experiencing these issues - false alarms, sudden braking, the system killing the accelerator because it thinks there's an obstacle - please post below, and we will try to get some more attention focused on this serious issue.
Current list of members (as of Aug 28) who have experienced this issue and cited it in either this thread or another:
1. Me, e400 wagon
2. Sunrose 305, e300
3. Brittnie jane, C300
4. Diesel Dan, e550
5. RSnovi, glk250
6. DDgator, glc
7. Bert.DS glc350e
8. Senatov
9. Frandumont glc300 (dirty sensors?)
10. Mickhoog
11. The_Judge e400 coupe
12. sackboydad, e450 cab
13. Streamliner, s560
14. Absent, s560 (loaner)
15. Malmokalle, e class
16. MBZ2019, a class
17. Legume, e400 wagon
18. Darren Boey, C350e
19. Utsenmo, C300
I am the owner of a 2018 e400 wagon. My vehicle has persistent "false alarm" activation of the radar-driven safety systems, including the emergency braking system.
I'm in communication with MBUSA on these issues. Their position is that the system is "operating as designed" and they are refusing to take action. They are also telling me that mine is an isolated incident, which I know to be untrue from other forum members sharing their same issues.
What I'd like to try to do is get more visibility into how much this is occurring. I've seen at least 3 other members with the same issue just in the E-class forums, and a few scattered around other models. Maybe if we get a large enough group together, who are all experiencing these issues, we can get MBUSA to step up and do the right thing - before someone gets seriously injured, or worse, by these issues.
So if you are experiencing these issues - false alarms, sudden braking, the system killing the accelerator because it thinks there's an obstacle - please post below, and we will try to get some more attention focused on this serious issue.
Current list of members (as of Aug 28) who have experienced this issue and cited it in either this thread or another:
1. Me, e400 wagon
2. Sunrose 305, e300
3. Brittnie jane, C300
4. Diesel Dan, e550
5. RSnovi, glk250
6. DDgator, glc
7. Bert.DS glc350e
8. Senatov
9. Frandumont glc300 (dirty sensors?)
10. Mickhoog
11. The_Judge e400 coupe
12. sackboydad, e450 cab
13. Streamliner, s560
14. Absent, s560 (loaner)
15. Malmokalle, e class
16. MBZ2019, a class
17. Legume, e400 wagon
18. Darren Boey, C350e
19. Utsenmo, C300
Junior Member
Joined: Feb 2023
Posts: 30
Likes: 1
C300 4Matic, DX1 Trim, AMG line, Panoramic roof, Black paint with grey interior
I’ve also experienced “very close calls”, complained to my MB Dealer who informed me that the system is operating as designed.
DaveRRR. 2023 C300
DaveRRR. 2023 C300
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Senior Member
Joined: Jan 2019
Posts: 489
Likes: 161
From: Philadelphia area
2014 SL65 AMG, 2018 S560
I would not hold my breath for MB to reverse course.
This issue can be easily mitigated with STABLE VOLTAGE.
The chassis uses Bosch variable voltage BUT IS NOT COMPLIANT with variable power supply.
The unstable voltage cause modules to downgrade bandwidth speeds of CAN networks.
You can experimentally unplug ALT LIN under 5mn to find out the WHOLE CHASSIS RUNS BETTER including :
Rebooting chassis will restart voltage adaptations by CAN Modules.
Once you're done dealing with unstable voltage, you can look into "oil pump solenoid" limiting pressure under 3500.Rpm...
This issue can be easily mitigated with STABLE VOLTAGE.
The chassis uses Bosch variable voltage BUT IS NOT COMPLIANT with variable power supply.
The unstable voltage cause modules to downgrade bandwidth speeds of CAN networks.
You can experimentally unplug ALT LIN under 5mn to find out the WHOLE CHASSIS RUNS BETTER including :
- the laggy/precise engine throttle
- tranny sloppy/perfect shifts
- the ESP brakes "limited..." faults
- the ghost/sensitive radars
- unstable CAN-Bus networking
Rebooting chassis will restart voltage adaptations by CAN Modules.
Once you're done dealing with unstable voltage, you can look into "oil pump solenoid" limiting pressure under 3500.Rpm...
I started by putting a new main battery in the car. The problem went away for a few months and then started again. Testing the new battery for CCA I found that it had lost a lot of its power and was looking more like a several years-old battery than a several months-old battery. That's when I started using the voltage logger. What it made clear was that the alternator was overcharging the battery and damaged it. I suspected the voltage regulator and decided to just replace the alternator. For good measure I also replaced the battery sensor. On most newer MB vehicles the battery sensor is integrated into the negative battery cable. The problem has been gone now for over a year.
If you're going down a similar path get your battery tested first. Beyond that I suggest replacing the battery sensor first. Unlike the alternator, it's fairly cheap and very easy to replace.
Out Of Control!!
Joined: Apr 2019
Posts: 12,058
Likes: 6,848
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
The Instrument Cluster can be setup to display the live VOLTAGE through the shop menu.
It's interesting to witness if voltage drops in the 11Volt range in case the battery is being drained by driving or not.
Normal range is
12.6V float up voltage
14.9V bulk rapid charge
12.3 is abnormal battery drain while driving.
It's interesting to witness if voltage drops in the 11Volt range in case the battery is being drained by driving or not.
Normal range is
12.6V float up voltage
14.9V bulk rapid charge
12.3 is abnormal battery drain while driving.
Senior Member
Joined: Jan 2019
Posts: 489
Likes: 161
From: Philadelphia area
2014 SL65 AMG, 2018 S560
The Instrument Cluster can be setup to display the live VOLTAGE through the shop menu.
It's interesting to witness if voltage drops in the 11Volt range in case the battery is being drained by driving or not.
Normal range is
12.6V float up voltage
14.9V bulk rapid charge
12.3 is abnormal battery drain while driving.
It's interesting to witness if voltage drops in the 11Volt range in case the battery is being drained by driving or not.
Normal range is
12.6V float up voltage
14.9V bulk rapid charge
12.3 is abnormal battery drain while driving.
This may not show up on a display because of smoothing. My logger took a voltage reading every 1/10 second and recorded to a log file.
Do you have instructions on how to get the voltage to display?
Out Of Control!!
Joined: Apr 2019
Posts: 12,058
Likes: 6,848
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
If you can get voltage readings then a good test of the battery is to watch the voltage during engine start. Before I replaced the "new" (but now damaged) battery, the logger showed voltages in the 8-10V range during the start. After replacing the alternator and the battery sensor, I replaced the battery again. The start voltage then remained in the 12.5V range.
This may not show up on a display because of smoothing. My logger took a voltage reading every 1/10 second and recorded to a log file.
Do you have instructions on how to get the voltage to display?
This may not show up on a display because of smoothing. My logger took a voltage reading every 1/10 second and recorded to a log file.
Do you have instructions on how to get the voltage to display?
It needs to be setup each time BEFORE starting the engineneith the steering wheel side buttons. Search youtube!
A simple eay to gauge how weak your battery is, listen to the engine cranking speed.
