auto Box won't shift C200 w203

[RWD66]

Hi. I'm sure you've all seen this situation before and hopefully someone can come up with a solution.
I have a C200 2 litre auto W203. It had the issue when I bought the car.
I can get the lever to shift from park to drive. On engaginging it gives a good wallop, even when put in reverse. Start driving and it will not shift up and stays stuck in first.
Read codes on it and it came back as incorrect gear ratio plus tcm. Opened the sump and found the module in a bit of a state. So went out and bought a complete used gearbox from another exact model. Changed the module. Drove the car and it started to shift. However got in the following day to drive and back to square one:sad::sad::sad:. Read the code once again and came up with incorrect gear ratio . The tcm code has gone.
It will not shift manually either, nor will it switch between over into sports mode.
The oil and filter are fresh so I guess I can rule that out.
Anyone out there who knows what the problem is?
Solution will be more than appreciated.
Thanks

 

[television]

If the tiptronic box, do you have the gear in the instrument display, like P when in park.

 

[whitenemesis]

Was STAR used to read the codes?
Have you checked for atf in the loom, a leaking pilot bush? Check the TCM for oil contamination. Located under the kick panel in the passenger foot well.

 

[RWD66]

If the tiptronic box, do you have the gear in the instrument display, like P when in park.

Yes the instrument panel displays P R N D with W and that's all.

 

[RWD66]

Was STAR used to read the codes?
Have you checked for atf in the loom, a leaking pilot bush? Check the TCM for oil contamination. Located under the kick panel in the passenger foot well.

Hi. No. Memoscan was used. Gonna sound a bit thick now. Where is the pilot bush and are we talking about the loom coming out the unit in the sump of the box? Will check the tcm in footwell. Thanks.

 

[television]

Oil in the loom from the pilot bush cannot affect any gear changes. There is a connector on the side of the box that connects the transmission electro plate to the gearbox ECU. The bush is known to leak and new seal available.

Being stuck in one gear is usually a speed sensor faulty on the speed plate thats bolted the the valve block.

 

[dog68]

Check the wiring at the idle control.

 

[whitenemesis]

Hi. No. Memoscan was used. Gonna sound a bit thick now. Where is the pilot bush and are we talking about the loom coming out the unit in the sump of the box? Will check the tcm in footwell. Thanks.

Really should get the codes read using STAR, far more in depth and meaningful wrt MB.
Yes the pilot bush is were the loom enters the gearbox sump, well known for leaking and allowing atf to wick up the loom into the TCM. Not uncommon to find the TCM full of atf, which can disrupt operation and communication. The TCM can be restored by washing out the atf and replacing the loom and pilot bush.

 

[Wingnuts77]

Hi, I have the exact same issue. This started back around October last year. The only stand out difference is that it stopped working while I was driving it; I had stopped at traffic lights, probably still in gear too, but not sure. When I pulled off it felt sluggish and then didn't change gear.

I did have a mechanic look at it, in so much that he read the codes and reset some or even all of them. It then changed gear OK, but only until I turned it off, this was late 2019. I've barely used it since then, and then only within a 2 mile radius. About 2 weeks ago I had stopped, at which point it was still in drive but it wasn't engaged. I turned it off and on and it went back to it's current state. Since then it's been the same as the OP to the letter.

Currently I have only checked the ATF level which was OK, but I'll do it again just to be sure.
I'll also have a look at the TCM this weekend too.

Is my next move to get the codes read using a STAR? What should that cost roughly?
Like many others I'm currently out of work and I'm a complete novice when it comes to cars etc but I cannot afford to pay someone to do this.

Any help would be very much appreciated.

Thanks.

 

[Wighty]

Hi, I have the exact same issue. This started back around October last year. The only stand out difference is that it stopped working while I was driving it; I had stopped at traffic lights, probably still in gear too, but not sure. When I pulled off it felt sluggish and then didn't change gear.

I did have a mechanic look at it, in so much that he read the codes and reset some or even all of them. It then changed gear OK, but only until I turned it off, this was late 2019. I've barely used it since then, and then only within a 2 mile radius. About 2 weeks ago I had stopped, at which point it was still in drive but it wasn't engaged. I turned it off and on and it went back to it's current state. Since then it's been the same as the OP to the letter.

Currently I have only checked the ATF level which was OK, but I'll do it again just to be sure.
I'll also have a look at the TCM this weekend too.

Is my next move to get the codes read using a STAR? What should that cost roughly?
Like many others I'm currently out of work and I'm a complete novice when it comes to cars etc but I cannot afford to pay someone to do this.

Any help would be very much appreciated.

Thanks.

What mileage is the car at now ?
When was the last Gearbox ATF and filter change (recommended every 40k)
When you say the atf level was checked and ok , was it checked hot , engine running , in park ?

 

[LostKiwi]

Sounds like a conductor plate is missing a speed signal but you need Star to confirm that.

 

[leonrsa]

I had the exact same problem as yours. My display on the dash did not show the mode selected i.e. S(Sport)/C(Comfort), or whichever modes your car displays, such as Summer/Winter. (This may help with your diagnosis)
Without rambling on too much, the culprit was the gear selector assembly. I replaced it with an used unit, and the problem was solved.

 

[Wingnuts77]

What mileage is the car at now ?
When was the last Gearbox ATF and filter change (recommended every 40k)
When you say the atf level was checked and ok , was it checked hot , engine running , in park ?

Hi, sorry for the delay in replying, the notification was in junk.... let's hope I don't make too many of these school boy errors.

Mileage about 165k
Last change about 2 years ago, which would be about 20k. I can dig out the paperwork if you need me to be more accurate.
I checked it with a dip-stick that I had to purchase, it was in park and not running, I can't remember if the engine was hot or cold.

Obviously I can check it again, under which conditions are preferable?

Thanks very much for your reply.

 

[Wingnuts77]

Sounds like a conductor plate is missing a speed signal but you need Star to confirm that.

Does it have to be a STAR or can another machine do the same job? I ask as I don't think the mechanic has a STAR machine, but he does have something similar, and it looked decent enough if you know what I mean.

Thanks for your reply, clearly this is all new to me, but I cannot see why I shouldn't be able to fix this myself from the research I've done so far, at least I hope I can.

 

[Wingnuts77]

I had the exact same problem as yours. My display on the dash did not show the mode selected i.e. S(Sport)/C(Comfort), or whichever modes your car displays, such as Summer/Winter. (This may help with your diagnosis)
Without rambling on too much, the culprit was the gear selector assembly. I replaced it with an used unit, and the problem was solved.

I have had the radio out to fit a Bluetooth receiver, which entailed removing quite a lot of the housing around the gear lever, could I have broken or made a connection loose in doing this? Although, fitting the Bluetooth receiver and the gear issue must be at least 2-3 months apart, if not more. Additionally, nothing has been spilt on or around the center console.

 

[Wighty]

The lack of use isn't going to help the car , MB's hate a low battery voltage .
The ATF level needs to be checked hot , on level ground, engine running and in Park.
As far as diagnostics, it can be cheaper in the end to visit an MB specialist who knows these cars .
Icarsoft readers can be picked up second hand at just before £100 and are MB specific .