E class wont go from D to R. Error codes P1856 and C404

[otleygas]

Hi. I wonder if anyone can help

I have a 2007 E280 CDI Sport estate (Auto). The car starts and drives fine. The problem I have is that after driving I cannot move the auto gear stick from Drive into Reverse or Park, without first switching off the engine. If I turn the engine off and restart it, it then lets me move into reverse or neutral.

I took it to my local garage today who think it might be a problem with the gear selector control module (part number A2112674224). They found 2 error codes:

P1856 - shift lever position detection failed
and
C404: No can message received from control module

they phoned MB to check and MB advised that the unit has to be replaced by a MB dealer as a new one (apparently about £450 from MB) needs to be specially programmed to work with the car.

Before I spend money on what could be an expensive (£1k?) fix from an MB dealer:

is a faulty module the most likely cause of the fault and replacing it likely to solve it?
is it right that a new module has to be 'programmed in'? - could I just get a second hand unit from and get my local garage to swap it in?

Many thanks

 

[bertb1]

Hello
Find a MB specialist and get the car read properly
You can always get the part scn coded to your car


Sent from my iPhone using Tapatalk

 

[Adrian Montagu]

Hi
I have the same problem with a W211 E280 cdi V6 2006 facelift
I get this as an intermittent fault.
Sometimes I lose the ability to use gears manualy.
If I take my foot of brake pedal I can move the gear lever.

Did you fix the problem?

 

[LostKiwi]

Hi
I have the same problem with a W211 E280 cdi V6 2006 facelift
I get this as an intermittent fault.
Sometimes I lose the ability to use gears manualy.
If I take my foot of brake pedal I can move the gear lever.

Did you fix the problem?

That sounds more like a bad or incorrectly wired brake switch..

 

[Adrian Montagu]

It's an intermittent fault and I have replaced the brake switch.
It also affects the ability to use the gears manually and sometimes prevents the brake hold from working (like when you are on an uphill slope and press the brake hard). My thoughts are that there is something more to this like a resistor failure at one end of the canbus. or a poor earth. I also have a report of low voltage for the tailgate. Mercedes comments, which are stored, state that "if the customer doesn't complain about this ignore it." I have also had extraneous faults like the radio starting to go quiet. There is something quite weird going on.