Noticed on many Mercedes models.
First if all,getting the error codes scanned from the computer is advisable.
In many of such cases,there is error code stored in computer memory of car.Getting the Mercedes scanned helps to retrieve the codes.If there is no error code retrieved,then further troubleshooting is required.
One very common failure I have found with the transmission problem you have listed here is the transmission valve body itself.This valve body is electrically and hydraulically controlled and also integrates the transmission computer inside of it.
This valve body is located in the bottom of the transmission.In most cases this valve body fails and causes this problem here and cannot be repaired and has to be replaced as an entire valve body unit.
Most likely this is what is failing on this vehicle as this is very common on these models with the newer 722.9 transmissions.
If your vehicle is under warranty then this would be replaced free of charge,if it is out of warranty then it wouldn't be covered and would have to be paid by you.You can contact Mercedes customer service for two things here.
You can contact them to let them know the dealer is not fixing the vehicle or is denying the problem and they will light a fire on this problem with the dealership.You can also ask since you have had to go to the dealer a few times for this and nothing has been done will Mercedes help pay for this repair,they are generally fairly good about helping cover the costs of these repairs especially in these situations.
Most likely this is what is causing this problem as I have run into this several times before.
This transmission valve body houses the computer and the electronics for the transmission as well as the hydraulic shift components and has to be replaced as a complete assembly.Many a times while getting the transmission oil/fluid replaced,the dirt/dust gets freed up some debris in the valve body while changing the fluid and cause this to happen since this problem.
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First if all,getting the error codes scanned from the computer is advisable.
In many of such cases,there is error code stored in computer memory of car.Getting the Mercedes scanned helps to retrieve the codes.If there is no error code retrieved,then further troubleshooting is required.
One very common failure I have found with the transmission problem you have listed here is the transmission valve body itself.This valve body is electrically and hydraulically controlled and also integrates the transmission computer inside of it.
This valve body is located in the bottom of the transmission.In most cases this valve body fails and causes this problem here and cannot be repaired and has to be replaced as an entire valve body unit.
Most likely this is what is failing on this vehicle as this is very common on these models with the newer 722.9 transmissions.
If your vehicle is under warranty then this would be replaced free of charge,if it is out of warranty then it wouldn't be covered and would have to be paid by you.You can contact Mercedes customer service for two things here.
You can contact them to let them know the dealer is not fixing the vehicle or is denying the problem and they will light a fire on this problem with the dealership.You can also ask since you have had to go to the dealer a few times for this and nothing has been done will Mercedes help pay for this repair,they are generally fairly good about helping cover the costs of these repairs especially in these situations.
Most likely this is what is causing this problem as I have run into this several times before.
So if you have near by recently if got the transmission fluid replaced,and after that if problem started then get the valve body properly flushed/cleaned.
This details will help.
Thanks.
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http://technoanswers.blogspot.com/2012/01/automatic-transmission-shift-lever-hard.htmlFor more transmission solution help, check the list mentioned below: -------