HI I have a 2014 MB CLA 250 4matic and the problem is I can put into gear from P when start up the car to D or other gear positions but when i want to park my car I couldn't put it back to P the only two things i can do is stop the car and push it to N position and switch off the key and take it out so it will automatically switch to P position or stop the car and open the door it will automatically switch to P position. Can you please help how to fix this problem.
Thank you very much
Thames74
It seems to be an electronic issue. Mercedes are over engineered. I would look into Mercedes forums about this issue and find an independent mechanic who works on these to find/fix the issue.
I looked every where in the MB forum but no luck on this issue
However the code from scanner was U0212-00 and also U1420-00
Good luck indeed... Most likely not to be of a mechanical fault. If it be the TCM you looking at at least 1k for the part, 2-3k for repair. Could also be the Trans shift solenoid. Also an expensive repair. Both of those do go out. Use to work at a benz shop. Wouldn't be the first time. See if you can scan for codes at a benz specific shop. They should have the STAR program to help you run though it.
I had it scanned the code is U0212-00 and also U1420-00
That's very common on these GETRAG built dual clutch transmissions.
The "Mercedes 7G-DCT" is basically a fancy more complex "VOLVO MPS6" which is once again a fancy more complex "FORD Power-Shift"
There was a common issue back in 2008-2013 where the TCM ground connection would be poor and intern this would cause the transmission computer to communicate poorly with the rest of the car.
If your car has the Auto-Start-Stop functionality: on your transmission you have two independent oil pumps - one electric and one mechanical. these oil pumps are responsible for shifting gears. Go to manual shifting mode and go between first and second to see if the shift quality differs if your engine is on and if your engine is off.
There's a solid chance that your transmission actually can't go into Parking at all, try to shift into P (without the E-break) and push your car to see if does roll more then 30-50 cm before the wheels lock up (On GETRAG dual clutches, a bit of rolling before the wheels lock up is normal) (at your own risk, this obviously could go badly including the Praking pin getting stuck or it rolling away and much more fun!)
Also a quite common issue is the shift knob being broken. move the shift knob to see if it does immediately display on screen.
To get the most accurate results, you need someone to plug in a modern high-end scan tool. there's a good change that this will be able to pin point the exact solenoid or tell you if there's a commutation issue.
It could end up being just a regular good old valve body faliure, but there typically happen after 90k miles.
From my personal experience with the MPS6 (from my VOLVO that's currently in a transmission shop for a clutch job) It's very hard to diagnose issues as they're very complex unlike their simpler brethrens - the Ford PowerShift and Renault EDC6.
A video could be helpful. would be glad to know the results of any tests.
take it only into a shop that has a lot of experience with Mercedes and Volvo dual clutches, it's a very complex job that required specialized tools and a lot of experience to do correctly.
I had it scanned the code is U0212-00 and also U1420-00. However every working fine the only thing is when I want to park the car it not letting me push back to P position
These codes just mean your shift selector P button / position is broken.
U0212-00 - "Lost Communication With Steering Column Control Module" - means your shift selector doesn't send the correct message when you put it in P
U1420-00 "Implausible Electronic Gear Select Signal Received" - means your shift selector doesn't send the correct message when you put it in P
I do not have wiring diagrams for the Mercedes A class so I do not have advise on what wiring to check.
I'd honestly just replace the whole gear selector and it's wiring.
My Volvo with the same gearbox type (GETRAG 6DCT450 on Volvo and 7DCT300 on Mercedes.) had this fault when it was newer, It had "Shift position hall effect sensor" and for me it was just a matter of reconnecting the harness.
The codes have the answer for you - they almost definitely indicate a broken shifter.
Check wiring, Replace the shifter, done.
(Change oil every 40k miles, otherwise the 7DCT300 will not last)
Thank you for your advise so you mean I have to replace the whole gear shifter selector on my steering wheel because I look in eBay there was a part they sell just only the lever selector do you think it would work or it has to be replace the whole column
I personally do not know, It may require reprogramming with special dealer exclusive tools and I'm not sure what Mercedes benz's policy is on costumer provided parts.