W221 722.9 gearbox issues
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Joined: May 2020
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s320L
W221 722.9 gearbox issues
Need advice on the gearbox issues started on s320 few days ago. It all started at some stage, when all of a sudden car got stuck in limp mode. Engaging drive or reverse went it with jolt and was driving only in one gear. Car went to gearbox specialists who found p2716, which is Y3/8y4 K3 clutch control solenoid. They cleared the error memory and did reset all adaptations and car was driving fine, except it would keep it all the time in low revs.
Today after starting the car all gears seemed to start banging again, gears were slipping and gearshifts were with delay and bang and eventually car lost all its gears, putting into D or R did not engage. Now it does engage in gears however is same like before with bang and limp mode.
Since mechanics and “specialists” here have no idea what they are doing, what would be first step in eliminating issue?
Im thinking about sending TCM to england for repair, however most places only fix speed sensor faults, not p2716. Valve body should also be inspected along with solenoids?
Also considering ordering another gearbox, but it looks like i would still need another TCM, and some people say they will never shift smooth....
Long story but a lot of trouble
Today after starting the car all gears seemed to start banging again, gears were slipping and gearshifts were with delay and bang and eventually car lost all its gears, putting into D or R did not engage. Now it does engage in gears however is same like before with bang and limp mode.
Since mechanics and “specialists” here have no idea what they are doing, what would be first step in eliminating issue?
Im thinking about sending TCM to england for repair, however most places only fix speed sensor faults, not p2716. Valve body should also be inspected along with solenoids?
Also considering ordering another gearbox, but it looks like i would still need another TCM, and some people say they will never shift smooth....
Long story but a lot of trouble
Out Of Control!!
Joined: Sep 2018
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From: unbegrenzt
2017 GLE350 4MATIC
How many miles/kms?
Read this site, common failures include conductor plate/solenoids and torque converters.
Speed sensors and TCM failures seem less commonly reported. But not impossible.
From your description it sounds like hydraulic/mechanical issues which to me seems like either conductor plate or torque converter. While expensive, both are replaceable.
You need to be working DIY with a XENTRY/DAS system, or your mechanic needs to be using this system. Third party diagnostics will not suffice for this.
Read this site, common failures include conductor plate/solenoids and torque converters.
Speed sensors and TCM failures seem less commonly reported. But not impossible.
From your description it sounds like hydraulic/mechanical issues which to me seems like either conductor plate or torque converter. While expensive, both are replaceable.
You need to be working DIY with a XENTRY/DAS system, or your mechanic needs to be using this system. Third party diagnostics will not suffice for this.
Super Member
Joined: Feb 2007
Posts: 601
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From: Republic of Texas
W203 W212 W211 R53MCS
Are you experiencing any issues with ESP/ABS??? The most common failure is the conductor plate/TCU. Usually you will get internal speed sensor codes failures, no communication from TCU and also codes for solenoid, but it is the plate not the solenoid. Do you have access to Xentry?? If you do a full scan with Xentry, send me the report and I will take a look at it.
Newbie
Joined: Feb 2020
Posts: 5
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S55 AMG
I got code P2725 after going into limp mode same symptom as guy with S320,I have 08' S550.
Drained converter and pan 2x fluid wash dark almost black and refilled with Valvoline max life full synthetic.
I was told it was ok to use but dealer said it contaminated the tranny and the thing needs to be replaced.
Sill drives fine with power on city streets just wont get outta 2nd gear.
Also the eletrical connector on the conductor plate came off while taking valvebody down.
was able to get it back connected to the plate but dont know if that would make a difference since after all that and
then changed and tested out all solenoids it still drives the same as it did before the first flush of black fluid.
Dont know what to do a this point im considering swapping another tranny out.
Drained converter and pan 2x fluid wash dark almost black and refilled with Valvoline max life full synthetic.
I was told it was ok to use but dealer said it contaminated the tranny and the thing needs to be replaced.
Sill drives fine with power on city streets just wont get outta 2nd gear.
Also the eletrical connector on the conductor plate came off while taking valvebody down.
was able to get it back connected to the plate but dont know if that would make a difference since after all that and
then changed and tested out all solenoids it still drives the same as it did before the first flush of black fluid.
Dont know what to do a this point im considering swapping another tranny out.
Out Of Control!!
Joined: Sep 2018
Posts: 14,663
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From: unbegrenzt
2017 GLE350 4MATIC
The transmission is an fill-to-overlow-at-temperature system. Did you refill using this method? If not, it could be possible the fluid is low. Search this site, this is extensively covered. Also look at Senior Leigh''s videos on YouTube and his website. The electrical connector could be problematic. Can you post photos?
Newbie
Joined: Feb 2020
Posts: 5
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S55 AMG
I'll post a pic of what came off the plate,and also the codes being ran on something called ''torque plus''scanner which probably isn't good enough but mercedes scan said ''faulty B2 solenoid and the torque scan said "pressure control solenoid E.
Also have ABS/ESP inoperative on dash since buying the 300 miles ago,drove fine before jerking on the freeway once then straight limp mode after a restart.
Transmission fluid got changed by dealer couple days ago.
Idk what kind they wouldnt tell me just said "its the right fluid now and car is driving fine for now''
This is after telling my the transmission is ruined and needs a new one.
They never said anything about the conductor plate or solenoids i changed
These dealer services are just scams they wouldnt even check all the codes on the car before suggesting a new tranny.
Also have ABS/ESP inoperative on dash since buying the 300 miles ago,drove fine before jerking on the freeway once then straight limp mode after a restart.
Transmission fluid got changed by dealer couple days ago.
Idk what kind they wouldnt tell me just said "its the right fluid now and car is driving fine for now''
This is after telling my the transmission is ruined and needs a new one.
They never said anything about the conductor plate or solenoids i changed
These dealer services are just scams they wouldnt even check all the codes on the car before suggesting a new tranny.
Last edited by Leandre Cook; Nov 20, 2020 at 06:26 AM.
Newbie
Joined: Feb 2020
Posts: 5
Likes: 1
S55 AMG
I'll post a pic of what came off the plate,and also the codes being ran on something called ''torque plus''scanner which probably isn't good enough but mercedes scan said ''faulty B2 solenoid and the torque scan said "pressure control solenoid E.
Also have ABS/ESP inoperative on dash since buying the 300 miles ago,drove fine before jerking on the freeway once then straight limp mode after a restart.
Transmission fluid got changed by dealer couple days ago.
Idk what kind they wouldnt tell me just said "its the right fluid now and car is driving fine for now''
This is after telling my the transmission is ruined and needs a new one.
They never said anything about the conductor plate or solenoids i changed
These dealer services are just scams they wouldnt even check all the codes on the car before suggesting a new tranny.
Also have ABS/ESP inoperative on dash since buying the 300 miles ago,drove fine before jerking on the freeway once then straight limp mode after a restart.
Transmission fluid got changed by dealer couple days ago.
Idk what kind they wouldnt tell me just said "its the right fluid now and car is driving fine for now''
This is after telling my the transmission is ruined and needs a new one.
They never said anything about the conductor plate or solenoids i changed
These dealer services are just scams they wouldnt even check all the codes on the car before suggesting a new tranny.
Arrow points to what came off my conductor plate but was able to put back on tightly.
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Out Of Control!!
Joined: Sep 2018
Posts: 14,663
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From: unbegrenzt
2017 GLE350 4MATIC
@Leandre Cook Who did the transmission fluid change? Did you do the work? Or did the dealer do the work? Your posts above are not clear. If the transmission is not shifting correctly after the dealer or repair shop changed the fluid, take it back to them and have them fix it.
If you were able to tighten the connector, this could mean it is not broken. The question remains as to how it became loosened. How many miles are on this vehicle?
If you were able to tighten the connector, this could mean it is not broken. The question remains as to how it became loosened. How many miles are on this vehicle?
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Newbie
Joined: Feb 2020
Posts: 5
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S55 AMG
@Leandre Cook Who did the transmission fluid change? Did you do the work? Or did the dealer do the work? Your posts above are not clear. If the transmission is not shifting correctly after the dealer or repair shop changed the fluid, take it back to them and have them fix it.
If you were able to tighten the connector, this could mean it is not broken. The question remains as to how it became loosened. How many miles are on this vehicle?
If you were able to tighten the connector, this could mean it is not broken. The question remains as to how it became loosened. How many miles are on this vehicle?
driving condition has been the same since after all the flushes. It has 83k miles
connector came off plate when pulling valve body down i think my mechanic tugged on it too hard and it came off the plate but stayed plugged in the other other end where the cord hangs from under the car
Last edited by Leandre Cook; Nov 20, 2020 at 09:28 PM.
Out Of Control!!
Joined: Sep 2018
Posts: 14,663
Likes: 4,567
From: unbegrenzt
2017 GLE350 4MATIC
Three fluid changes, correct? Do you think it's possible that damage occurred during the flushes? Possibly the connector was bumped, cracked or damaged in some way? You need to get to a known good condition somehow.
Are you 100% confident the fluid level is correct?
Are you 100% confident the fluid level is correct?
