SBC values in SDS, what do they mean?
So what do these numbers really mean? Is the SBC on it's last leg, or does it have life left? Should I replace the entire SBC with a $1,000 remanufactured one now, or can I fix the low pretensioning pressure by replacing the $100 accumulator?
DJ_GetBRLiveTime: 750608
DJ_GetPmpCycle: 27882500
DJ_GetPmpLD: 46.625008
SBC pedal value sensor: 18.0mm
Front axle pre pressure sensor: 7.7bar
Left front pressure sensor: 6.9bar
Right front pressure sensor: 7.3bar
Left rear pressure sensor: 0bar
Right rear pressure sensor: 0bar
Reservoir pressure sensor: 120.8bar
Pretensioning pressure of pressure reservoir: 68bar
Temperature: 42C




I did hear from MB technician that the number should be 600k before pump rebuild, but it is also affected by other factors, where pump cycles show the count as well.
Are you the original owner? I would think somebody erased something in computer?
Frankly the number would really worry me. If you decide to drive it for longer, go to empty lot and practice some emergency braking with SBC plug pulled.
What I'm trying to figure out is how to tell what the wear is based on the values? I.e. is the pump still strong, and is it just the accumulator that is leaking (which I can replace for cheap), or is the whole SBC unit worn out and I should replace it with a refurbished one.




https://mbworld.org/forums/showpost.php?p=7250102&postcount=1147
FWIW, I would replace the entire assembly as preventive maintenance. If not, just the accumulator. You can be the guinea pig to see how many actuations the SBC will go before it quits on you. Also, zero Bar pressure on right and left rear does not look right.
EDIT: no reason you cannot go into the dealer yourself and request to go over the service records. No reason they cannot redact personal info and make a copy for you.
New edit: looking at the attached document, part of Service 9 is to check the preload pressure of the pressure reservoir; that implies the accumulator.
Last edited by bbirdwell; Feb 13, 2018 at 03:56 PM.








I don't see them addressing transmission service and they only go to 150k miles, when my cars are above that

Suppose the first wearable on SBC are motor brushes, but again, MB rebuild whole units for a good reason.
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I guess my hangup is I don't understand why my SBC is reporting ~47% service life if the consensus is it should be worn out due to mileage and 750k actuations. I didn't want to replace an expensive part if it was unnecessary, but I'm thinking I may just eat the cost and order a new SBC so that I can be confidant in the car.
As for the service records, I'm only relaying what I was told. I went to the dealer in person, and the "specialist" informed me that it was against MB policy to share service records under any circumstance unless the original owner showed up in person with their driver's license to verify their identity.




https://mbworld.org/forums/e-class-w...pump-w211.html
Pump cycles old unit ~10M, pump cycles new unit ~18K. CDIJeff listed pump cycles but not the old unit actuations. New unit actuations (Bremsenzahler) were 1382.
and
https://mbworld.org/forums/w211-amg/...d-reached.html
Joe had ~556K actuations indicated on Bremsenzahler when it gave the white warning. He did not list the pump cycles old and new.
This is sort of like a puzzle....


