guapo

couple days ago my trans would not shift at all. would not engage in any gear and check engine light came on (P0715 input turbine speed).
-towed car home and changed trans fluid and filter
-trans now engages in forward and reverse (HARD INTO GEAR THOUGH)
-trans will not shift 9 stuck in 1st gear
-still have p0175 and cannot cleaar.

Is there a way to clear TCU, my Actron 9135 OBD2 will not clear. I hate to change the speed sensor plate and find out that all is had to do was reset tcu for trans

CA_Tallguy

Sounds like you are on to the potential problem. The electrics plate. It's really not all that hard to replace and if it hasn't been done, it's probably a good idea to take care of it. It isn't much harder than changing your transmission filter and fluid.

There is no way to reset the electronics without the mercedes diagnostics or something high end/professional like snap-on. Trust me -- I was in your shoes myself and searched and searched for a way. Disconnecting the battery is almost certainly not going to work. Tried that as some posts suggested, but it was futile.

If you are lucky, an indy shop might clear them for free but I'm guessing they won't do it because your car is in limp home mode to protect your transmission and you are risking damage -- or further damage -- by rolling the dice with a reset.

This happened to me at almost exactly the same time last year. I swapped out the electrics plate over thanksgiving holiday but couldn't find a shop open to reset the limp home mode. I did the battery thing, and also went to a service station where the guy claimed he could reset it. When I got there, he had nothing but a basic code reader and claimed he could do it. I said he was full of it and wasn't going to pay him to try. He said he was confident enough that if he couldn't do it he wouldn't charge me. Well, he wasn't able and claimed that he DID reset the codes and that it's because my car still had a problem. Of course, he tried to get me to pay him. He had no clue that Mercedes diagnostics went deeper than what you can access through ODBII.

Long story short, don't mess around. Transmissions are expensive and trying to run yours without a functioning speed sensor puts you at risk of destroying it. Swap the plate and go somewhere to get out of limp home mode when you are done.

CA_Tallguy

Also just wanted to add... you really should be breaking open your transmission anyway to change the fluid and inspect for any metal shavings or evidence of bigger problems before you reset the limp home mode. There is a chance you could have damage to the transmission from the slipping from not having a speed sensor working and opening it up may give you some idea based on what you find in the bottom of the transmission pan and in breaking open the filter. Also, make sure you inspect everything that comes out -- use something like a sheet or towel and run the fluid through it to see if you capture any large particles. So you might as well change the plate while you are in there.

Here's what I had in mine when I opened it up for this problem. I put it back together again as I had nothing to lose and it has been OK, thank god. But you don't want to be driving around with metal shavings swimming around in your tranny fluid.
https://mbworld.org/forums/e-class-w...on-filter.html

guapo

thanks tallguy,
your information provided was greatly appreciated. removed the plate and one of the speed sensors was cracked. installed everything back as specs unfortunately MB was unable to provide springs. I noticed that the shifting into R or D from N is alot smoother.
My friend has a SNAP-ON solus pro EESC316 (high end Scanner) hopes that it is sufficient to flash the trans computer. if not have to take it to STEALERSHIP.

CA_Tallguy

Sweet! Glad to hear it. Snap on scanners SHOULD be able to clear it -- can't say for sure if all models or only some, or if the scanner needs a mercedes/euro module for it to work. Sounds like it is a very good thing you switched the plate. It's only a matter of time on these plates before replacement so just a good thing to knock out. I suspect that big time damage can potentially happen with bad ones in there for a long time, though fortunately I think most people I've read about on here have not experienced anything too bad. Not worth the risk if you know exactly what it is and how easy it is to replace.

CA_Tallguy

If your friend's scanner won't clear it (if it is high end you should be in good shape though) you might try an indy mercedes/euro shop before the dealership. Some won't charge you, others will. It's a good business move in my opinion for these indy's to NOT charge. I'm taking my car in to the place that did it for me free for other work now. (They even checked my tranny fluid level for me since I hadn't used a dipstick to refill... and that was at their questioning/offer, not my trying to get free info or help.)

douglass44

I had the same problem in the past. I purchased a
MB Carsoft 7.4 Interface Multiplexed MCU Interface for Mercedes Benz

It does work and allows you access to reset your transmission computer. About the same as one reset at the dealer.


I purchased it for less than $100 at:


http://www.dealextreme.com/p/mb-cars...des-benz-16919

guapo

First of all thanks tallguy and douglass,

Took my car to dealership and they reset the computer for me. The trans conductor plate and harness conector was changed. The car trans worked fine for about a week.
The problem I have know is that when the car gets to 180 degrees. The trans slips out of D and I can only accelerate in P or N. I can only give it gas in P or N.
I have to shut the car off, wait a minute and then it will run in 2nd gear for about 5-10 seconds and then there is no gear engagement in any gear R or any of the D, 1,2,3,4. The trans then goes into limp mode. I had to repeat this process of shuting the car off and on repeatedly to get home about 2 miles from home.
In the morning the car runs in limp mode with 2nd gear on for as long as i want. I took car to indie shop. He resset the whole car and told me that it was not a trans or module problem but some electronics that interacts the two.
I am wondering can it be the wiring harness from trans to module or possibly the shifter. Is there a switch that prevents acceleration somewhere.
thank you once again guys.

ohlord

out the harness and the tcu? If it was leaking it may be full of trans fluid.
Diy on www.benzworld.org w210 forum

Rogair

guapo, how did you fix your tranny?

Plutoe

!

Rogair

Reset the whole car? Do you remember how? trans adaptation? I take it your friend's snap-on Solus scan tool did NOT work? I also replaced conductor plate after getting a p0715 code. Prior to replacement the car went into 2nd gear (electrical) limp mode, and won't come out, even with me using the solus to delete trans codes.... Now getting a P0748. Will dive into tranny TCU tomorrow. Thanx, for any input, sorry to dig up an old post...

Plutoe

Somebody did not do something correctly and or diagnosed the car incorrectly----0748 is a limp-home mode,one or more of the conductor plate solenoids is faulty-----sounds like a "doover"

FYI 0715 is the conductor plate speed sensor fault, which would correct with a new conductor plate

Rogair

Plutoe you are a God. I was confused since I had the same 'stuck in second gear' problem before and after but you're right... The solenoid closest to the electrical connector (pressure regulating solenoid I believe) looked like it was seated but when I pulled the conductor plate out the second time I realized that the solenoid was up about 30 thousandths from the plate- this is one of the two solenoids without O-rings and apparently it jammed in the aluminum valve body housing. I measured infinite resistance at the trans controller pins 36 &38; that's how I knew it was that solenoid... I posted on this forum because the SL / R 129 form was pretty much dead on the subject despite that it's the same transmission. Thanx again

vvrjrlaw

Plutoe can you tell me where you got your DAS XENTRY? There are a ton of them on the market and I'd like to pickup one that works. Thanks a million.

Plutoe

I put my two systems together my self(purchased the laptops, downloaded/installed the software and purchased the PART D mux's

vvrjrlaw

Thanks for the reply and please disregard the private message I sent you.

vvrjrlaw

My 2006 CLS55 amg did the same thing. Hard into gear, check engine light would stay on and trans would remain in 2nd. Cleared the check engine light and it went out until I shifted to D and on it came. Ordered a new shift conductor plate, new socket to the conductor plate, new filter ( third one in a year the trans is spotless) and gasket. The conductor plate was cracked and after making the changeover ( had to move all the solenoids and install them on the new conductor as well as the new socket) there was still the issue of clearing the code. Since the code was sent to the transmission control module I either had to go to the dealer (85 mi one way and 150.00) or look for a high end scanner to do the job since most scanners will only clear the engine control module but nothing else. My friend who does my work when I can't owns a high end shop and a MAC scanner that cost him 4500.00 and voila hooked it up counted 20 stored codes in the TCU cleared them all and the car runs like a bandit. There is no cheap way to fix it but if you buy the kit it will cost under 200.00 (plate,gasket socket and filter all OEM) plus fluid and assuming the solenoids are ok ( find the the You Tube video it rocks) and it costs you 150 to clear the code ( some dealers will do it for free as goodwill) the job is done for under 500.00 in parts. Good luck.