1999 SL500 trans fault

[jeff0093]

Hi Guys looking for advice another shop is having a issue with this car and he asked me for some advice, he did a trans service and filter. This is the only code that is coming back after we scanned it for him is this one. Let me know what you guys think

 

[alabbasi]

I think that this is a speed sensor code. The 722.6 is a tough transmission. I would suspect that the conductor plate may be acting up. This is the electronic component of the transmission. New conductor plates are under $200 and solve a lot of problems. There's also an O ring that needs replacing. Other issues that can cause it to go into limp home mode is the brake switch which will trip the ASR warning light.

Hopefully they're using the correct (236.10-236.14) fluid.

 

[gsxr]

Here you go:

https://www.google.com/search?q=mer...rome..69i57.2431j0j8&sourceid=chrome&ie=UTF-8

If the conductor plate is original, decent chance a new one will fix it. Don't forget to also replace the connector wingding which goes between the plate and the wiring harness; this includes the new O-rings that I believe MB no longer sells separately. The connector is cheap. The pan gasket can be re-used assuming a new one was just installed, ditto for the fluid if it's drained into a clean container. Messy job all around.

 

[jeff0093]

ok, we did the google thing and it looks like that conductor plate fixed some and not others, I think he ended up using Redline D4 ATF, should he not use the Redline fluid?

 

[alabbasi]

Redline is fine.

 

[gsxr]

Red Line D4 is what I use in both of my 722.6 transmissions. Good stuff, zero issues, and it's what I'd recommend.

I would have sworn their website used to state that D4 was equivalent to MB 236.10 spec, but it no longer makes that clear... maybe MB legal hassled them? I'll have to read the lablel on the jugs in my shop, maybe it says on there. The website still says MB 5-speed / NAG-1, which is the 722.6 trans:
http://www.redlineoil.com/product.aspx?pid=51&pcid=9

 

[lowman]

you will also need to check the sensor wheel for the speed sensor ...there is a bearing inside that mainshaft..that can wear out..and the mainshaft sinks down in the middle..and the sensor wheel touches the speed sensor in the conductor plate.

 

[jeff0093]

yeah we have been using D4 and D6 for years with good results, just double checking for this application

 

[jeff0093]

OK, I just ordered 140 270 11 61 AT Conductor Plate and 203 540 02 53 AT Plug adapter (with O ring) both OEM

 

[jeff0093]

No we did it, after changing the conductor plate and plug adapter we are getting no faults, but the transmission will not engage any gear, we dropped the pan a second time and nothing looks out of place. We shifted threw the gears and everything looks fine. Any advice??

 

[alabbasi]

Put the old conductor plate in and if everything wakes up again, you probably have a duff part. 722.9 valve bodies require programming, as far as I know (from experience) 722.6 do not.

 

[gsxr]

722.6 does not require any programming after a conductor plate change. Very odd there is no movement in any gear. And no codes? Fluid level checked, etc?

 

[jeff0093]

yeah no programming, I got a hold of Klink and I think we figured it out. We had to stop on it till tomorrow. thanks Jeff-

 

[gsxr]

Sounds good - please keep us posted, would like to know the root cause!

 

[lowman]

No we did it, after changing the conductor plate and plug adapter we are getting no faults, but the transmission will not engage any gear, we dropped the pan a second time and nothing looks out of place. We shifted threw the gears and everything looks fine. Any advice??

Are you SHURE that you got the plastic shifter fork in place ON the pin on the selector mechanism i told you about?sounds very much like this is your culprit.

 

[lowman]

Here is the plastic shifter "fork" im talking about,IN the RED circle.
The selector mechanism PIN HAS to go into that groove in that plastic shifter fork...if not.then you can get this issue you are talking about.

 

[Klink]

Here is the plastic shifter "fork" im talking about,IN the RED circle.
The selector mechanism PIN HAS to go into that groove in that plastic shifter fork...if not.then you can get this issue you are talking about.

Yep, that's what we discussed, too. Thanks for the photo.

 

[lowman]

nice one

No problem

 

[jeff0093]

I'll update as soon as I know the fix, unfortunately I'll be attending a funeral tomorrow, so it might not be till Monday.