Hello, I have a w212 facelift 7 g tronic + 2013 year om 651, I bought the car two years ago with kicking gears from 1 to 2, from 2 to 3, from 4 to 5 and vice versa, the strange thing is that it does not kick every time, one day it is perfect one day no, I tried two second-hand gearboxes, the result of both was the same, a year ago I did a complete repair of the gearbox with the hydro and the valve body, the result is the same, from there the workshop told me that it was a software problem, I uploaded the latest software on the motor and the box and the same thing again, 2 months ago I took it to another transmission service, they did a complete repair and to this day the problem remains, those from the last service say that the car's computer was opened and something was done.

 

You have a facelift diesel W212 with 722.9 that frequently bangs its lower gears 1,2,3,4 on some days while other days perfect.

Multiple gearbox, conductors and adaptations failed to help this issue.


Sorry to read about all your helpless tranny troubles.

You chassis has now fully developed a CAN-Bus latency issue on one of its main modules.

It is simply impacting networking such that your tranny simply receives its commands late.

I can help you identify your faulty modules based on your report. Please scan the whole chassis for ALL faults including ALT voltage control.

 

Ok, on Saturday I will scan them and send them to you.

 

The only error it gives is this U042900, the battery is about 1 year old.

N68 - Electrical power steering (ES) -f-
MB object number for hardware 212 901 66 06 MB object number for software 212 902 89 07

Diagnosis identifier 000703 Hardware version 13/34 01
Software version 13/23 00 Boot software version 12/49 00
Hardware supplier Valeo Software supplier ThyssenKrupp
Control unit variant EPS212_MOPF_0703
Fault Text Status
U042900 Implausible data were received from the steering column module. _ S
Name First occurrence Last occurrence
Development data (Root_cause_of_DTC_failure_ID) 257 - VCD driver -
Steering wheel angle
range failure

---
Development data (Root_cause_of_DTC_activation_time) 472.50s ---
Development data (Root_cause_of_DTC_additional_data_1) 02 ---
Development data (Root_cause_of_DTC_additional_data_0) 0B ---
Development data (Environment_of_DTC_ISw_Stat_value) IGN_ON ---
Development data (Environment_of_DTC_EngRun_Stat_value) UNLIMITED ---
Development data (Environment_of_DTC_vehicle_speed) 6.00km/h ---
Development data (Environment_of_DTC_mean_voltage) 12.60V ---
Development data (Environment_of_DTC_last_start_up_test_time) 18.50s ---
Development data (Environment_of_DTC_steering_wheel_torque) -3.20Nm ---
Development data (Environment_of_DTC_requested_motor_torque) -5.20Nm ---
Development data (Environment_of_FC_DTC_board_temperature) 46.00°C ---
Frequency counter --- 7.00
Main odometer reading 0.00km 0.00km
Number of ignition cycles since the last occurrence of the fault --- 7.00

 

The fault you referenced is a bad SCM circuit... either solderless acting up or the painted GND.

I wonder what scanner are you using to only be getting ONE single fault ?? That does not seem right.

 

I use Xentry, today I will scan properly, where can I see including ALT voltage control?

 

ALT is controlled by the ECU.

I am surprised Xentry only finds one faulty module.

Once you fix SCM, your car is going to keep straight on highways instead of the way it is unstable now.

 

These are all the errors, the distronic has been removed.
what is SCM,and how to fix it, in what way?

 

Tell us more! Were you able to code out Distronic and still have cruise control?

 

The cruise control works, the distronic is missing because it had a front impact.

 

There you have it or some of it. Xentry has a summary screen that list all module pass/fail error status. You may get more clues from that screen.

The missing or faulty modules generate a high enough traffic that it disrupts the timeliness of the ECU shift order to TCU. Either directly on the CAN-C or across one of its gateways.

Realize that faults are not simply a log entry... DTC are about modules struggling to operate.
Unfortunately modules are not smart enough to go quiet after a while. The disruption stays active.

SCM is the "Steering Column Module" It is a stack of modules sandwiched below the steering wheel. They are built with limited reliability. Fixing that stack is a rewarding great idea, be it solderless or painted footwell GND posts. See my signature for pics. Right now your SCM may be disrupted just like TCU by your Distronic issue.

To get your CAN-C working normally for tranny shifts I would focuss on fixing the Distronic first then SCM.... can't speak of other faulty modules I don't see here. I need full list.


How to silence your Distronic faults without repairing....
-- Try coding out the function in CGW.
-- You want to end up with NO faults to regain lost network bandwidth.
​​​​​​

 

OK, I will try to fix the distronic, I need the module and the socket for it, then how to fix this error U042900?

 

I have one more question, live data sensor B19/7 shows 0 as a value, the car has DPF. DPF has not been turned off or removed.

 

As far as Diesel DPF... it has some kind off back-pressure sensor that requires maintenance. Someone may have disconnected the sensor that now read 0... ouch!

This won't cause networking issue but impacts engine running and thus can affect tranny shifting with unpredictable timings.

Find the Xentry summary screen to show us all modules faults... I will rank your error priorities.

 

OK, I'll check it, where exactly is this B19/7 sensor located?

 

here it is in full

 

Okay I read through your whole list. ESP is what's actively disrupting your CAN-C.


ESP screwing up ECU/TCU timings

As mentioned earlier try to code that feature out in CGW. possibly only allowed using a Launch Creader and not enabled in Xentry.

Fix that issue so ESP is fault free for a top chance your tranny work nicely

ESP is trying to contact a collision radar through a gateway that's causing traffic jams for ECU/TCU data.
ESP is the ABS module in charge of brakes... it's best for driving to keep it connected.

 

Ok I will try these days and what is CGW?

 

CGW is the Central Gateway module that is built into the front SAM module located near windshield wipers on facelift cars.

CGW manages the active features for the chassis and is used to inter-connect data between the various CAN networks.

 

Distronics is turned off by software, there are no errors, there are no changes in the gearbox, one is perfect, other times they kick, two errors remain.

 

After the software removal of the distronic, the errors are gone, after about 500 km, the shifting of the gears became quite good, there are very small jerks sometimes, my question is whether it is necessary to adapt to the old hydrotransformer and the gears or it does not make sense. The only error that remains is that of the steering column
U042900
Thank you very much to the CaliBenzDriver for helping me to dig up my case study.