hello!
I have a 2006 Ml500 which is throwing a code 2201: component Y3/8n2 Internal speed sensor VGS is defective
car's symptoms are: at random times, gets stuck in 2nd or 3rd gear until i restart it then its all fine
my question is: does this need a new valve body or would replacing the conductor plate fix the problem?
Thanks!!!

Mr The...

Here is what I would do:

First of all, no need to replace " whole valve body". Yes, the 722.9 Transmission has lots of FLEA's.

Second, you could have a issue with a shift piston for 2nd to 3rd gear. I would inspect it, but before the inspection. Sign up for Mercedes EPC(You need a PC running Internet Explorer with Oracle Java fully updated...-You CANNOT circumvent this-It will not work on another browser, or operating system!!!!).EPC is free, but it will ask for a credit card...

EPC link:

EPC-net Online

Look up the parts to your ML500 per the VIN number, and see what parts are available for the valve body. I understand Mercedes Had lots of issues with the conductor plate, and shift solenoids. I do not have a diagram on 722.9, and it is different from 722.6. If the code points to the speed sensor, more than likely is. They tend to blister on 722.6. Inspect the filters on each of the solenoids, and blow them out. If you are the only owner since 2006 you are okay, but their has been a influx of cheap Chinese solenoids. The solenoids will have BOSH embossed on them. Inspect the o-rings on each of the solenoids.

The valve body is heavy, so use a jack. If the valve body has aluminum bolts, I believe you have to replace them. You'll need a torque wrench too.

Martin

I have a document that could be of help, but it is 17megs in size.

or

you can Google it using this in your search "49188099 Mercedes Transmission 722.9"

Best of luck,

Martin

try this link for the above document-

http://www.mercedestechstore.com/pdfs/286_722.9/286%20HO%20722.9%20062504.pdf

good luck, chuck.

thanks guys for your replies
do you know where I can buy the conductor plate from other than the dealer? they are charging me $730 just for the plate. Canadian dealers are a ripoff
Any mercedes dealers on this forum I could buy this from?
has to be programmed by dealer it appears

If you pm me your VIN number I'll see what I can do tomorrow at work. I've been lurking on here for a while but this was my first post. I'm a master cert benz tech, I'll see what price I can do on the conductor plate, but yes, a dealer or someone with an SDS will have to program it. The part is dealer only because its a theft relevant part

MB issued a bulletin concerning this problem early last year. The fix is a conductor plate, which on the 722.9 transmission includes the ECU. The repair kit is PN 000-270-17-00. List price is ~ $425 US. The kit includes the conductor plate, filter, gasket, and valve body bolts. Add about $100 for ATF.

thanks everyone particularly ILUVMILS for your very detailed reply
questions:
would a bad battery cause this kind of code? possible at all? only reason i mention is because my auto wipers, automatic lights were all acting up until i unplugged main battery for 30 mins. transmission also started shifting way smoother, no jerkiness to it. im just wondering if this is related at all?
also where can i buy this part online? canadian dealers charge a LOT for parts....