ESP / SBC Communication fault

Andrew Technician New York Posted   Latest  
Tech Tip
Test Can Connection To A7/3N1 (Sbc Control Unit).

Just a tip on an emerging issue we are seeing with SBC units on the 211 chassis and possibly some 230 chassis vehicles as well. The pump/module is replaced for whatever reason - timeout, electrical failure, etc and a new pump is installed. When the new pump is installed C1611 sets in the ESP module and the ESP warning comes on in the cluster. When the old unit is plugged in the code can be cleared.

This is typical if the wrong SBC unit has been installed, i.e. one that belongs to another vehicle, but what is unusual is this has been happening with brand new units from the dealer. We have advised customers to order a replacement using the original unit's part number and request that no substitutions be made, and so far we haven't heard back from anyone who has done it that way.

There is an old bulletin on SBC units that doesn't apply to this issue, but so far we haven't seen a new bulletin from Mercedes. It's been a couple weeks since we've had a case like this so we may be free and clear, it has been an ongoing problem for 2-3 months.

Typical Concerns:


"C1611 Test CAN connection to A7/3n1 (SBC control unit). Changed the SBC ( just plugged it in), has the same fault. "

" Replaced sbc unit due to service life exceeded now I get C1611 can connection to sbc, control unit version does not match esp Replaced esp unit still same code "

"c1611 ,esp message,replaced sbc unit with new one C1611 Test CAN connection to SBC control unit (A7/3n1). "

"ESP fault after replacing new sbc C1611 Test can Connection to a7/3n1 sbc"

" replaced sbc hydraulic unit, bleed brakes xentry says programing ok, replaced sbc hydro unit twice w/ bosch reman and mb reman. original faults go away And faults in abs occur. swapped unit back to original and original faults come back and can faults go away. same issue with both reman units. original faults go away andd can faults appear "

" Replaced sbc control unit for pump time out ESP lights on C1611 Check the can connection to a7/3n1 sbc control module "

Robert Diagnostician
New York

Thanks Andrew. I’ve had that problem when installing a used unit. We now only use OE ones. Have not had any problems with OE ones yet. Thanks for the heads up that’s a great time saver.

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Owen Diagnostician

I have done many of these when I worked at the dealer around 2011. We had a special attachment that would connect to the SDS and plug directly into the SBC unit and load the software for the specific model. That may be how the dealership solves this issue. I have no idea how to do this in the after market.

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Robert Mobile Technician

I just ran into this on a e350 yesterday! Shop put a used sbc in it and it had codes in the sbc for can communication error with esp. Esp module had a fault for can communication error with sbc. I put I put the original SBC in the car just enough to plug in the electrical connector, and the faults were gone. The part numbers were only off by a digit. These things are plug n play if it's the

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