2004 S500 Tranny wont behave y3/8n4
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Joined: Oct 2013
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E320
2004 S500 Tranny wont behave y3/8n4
Today I have a new issue that is causing my transmissio to not shift up or not shift at all. This issue becamen suddenly after I started the car and it died instantly. I restarted the car and it drove normaly until I reached about 60 I noticed the engine speed at 3000 RPM. When I came to a stop and then drove again the transmission would not shift out of 1st. I then stopped and restarted the car then the transmission shifted ok keeping the RPM in the high teens. I got home and got my scanner out. There are no codes that would cause car to go into limp mode but I have a code saying component y3/8n4 is defective. The car when started dies instantly sometimes but restarts. Each time I restart the car I get different results for the tranny, still in neutral when in drive, won't shift past 5th, may not shift at all and may slip between gears, and a couple of times all was ok, no problems.
So I guess my y3/8n4 is gone but I am reading about problems with the conections to it??
Can someone explain the engine dying thing, how that's related ?
I am worried that something else is causing this like battery, mass air sensor or I have 2 other codes, (open circuit right front wheel sensor), (occasional yaw sensor faul. It clears up and returns. It is presently gone) these codes have been with this car for quite a while.
Any one been through this?
Any help understanding where to start would be greatly appreciated, Bruce
So I guess my y3/8n4 is gone but I am reading about problems with the conections to it??
Can someone explain the engine dying thing, how that's related ?
I am worried that something else is causing this like battery, mass air sensor or I have 2 other codes, (open circuit right front wheel sensor), (occasional yaw sensor faul. It clears up and returns. It is presently gone) these codes have been with this car for quite a while.
Any one been through this?
Any help understanding where to start would be greatly appreciated, Bruce
Last edited by brujan; Dec 31, 2019 at 10:21 AM.
Thread Starter
Junior Member
Joined: Oct 2013
Posts: 26
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E320
Thanks for the reply, The issue is only one, my transmission went goof ball. I have a brand new code y3/8n4 which is a bad module in the transmission, so says the code.
The long run-on is me explaining all the symptoms that have jumped up with this code.
I am telling the story of how the failure took place and possible relevant behavior of the car so that hopefully someone who knows can help me figure out what to do next.
Simplyput , the transmission is suddenly acting crazy along with a brand new code.
I have another code in ESP that is an open circuit code for right front wheel sensor. It has been there for a long time. I also occasionally have a code saying component b24/15 defective, but it comes and goes. It is presently not a current code.
I mention all these things in that they may be connected the the issue about the transmission.
The long run-on is me explaining all the symptoms that have jumped up with this code.
I am telling the story of how the failure took place and possible relevant behavior of the car so that hopefully someone who knows can help me figure out what to do next.
Simplyput , the transmission is suddenly acting crazy along with a brand new code.
I have another code in ESP that is an open circuit code for right front wheel sensor. It has been there for a long time. I also occasionally have a code saying component b24/15 defective, but it comes and goes. It is presently not a current code.
I mention all these things in that they may be connected the the issue about the transmission.
Thread Starter
Junior Member
Joined: Oct 2013
Posts: 26
Likes: 1
E320
Ok,
Codes are 2402, 2550 and 200A. These codes all appeared as soon as all tha bad Tranny behaviors began. 200A is saying I have a bad vgs module in the the Tranny. (Bad Y3/8n4)
I have read that it can be actually a 13 pin connector that is invaded with trans fluid.??
Codes are 2402, 2550 and 200A. These codes all appeared as soon as all tha bad Tranny behaviors began. 200A is saying I have a bad vgs module in the the Tranny. (Bad Y3/8n4)
I have read that it can be actually a 13 pin connector that is invaded with trans fluid.??
Thread Starter
Junior Member
Joined: Oct 2013
Posts: 26
Likes: 1
E320
Ok,
Codes are 2402, 2550 and 200A. These codes all appeared as soon as all tha bad Tranny behaviors began. 200A is saying I have a bad vgs module in the the Tranny. (Bad Y3/8n4)
I have read that it can be actually a 13 pin connector that is invaded with trans fluid.??
Codes are 2402, 2550 and 200A. These codes all appeared as soon as all tha bad Tranny behaviors began. 200A is saying I have a bad vgs module in the the Tranny. (Bad Y3/8n4)
I have read that it can be actually a 13 pin connector that is invaded with trans fluid.??
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Mercedes
pull the Tcu out of the plastic fuse box in the engine compartment to see if it’s wet with fluid . If so then your connector is leaking and causing the issue
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Thread Starter
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E320
Gee, thanks
I will check that. Is the Tcu on the right fuse box or left? This is a left hand drive.
I would like it to be a leak, but of course it's going to be the integration module inside the Tranny.
I will check that. Is the Tcu on the right fuse box or left? This is a left hand drive.
I would like it to be a leak, but of course it's going to be the integration module inside the Tranny.
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From: Ball Ground, GA (N of Atlanta)
2003 S500 2007 GL450
The TCU is located in the Right SAM - remember that right/left is defined in vehicles from the viewpoint of the seated operator, so the RIGHT SAM will be on your left as you stand in front of the car.
Examine the wire harnesses inside the SAM carefully, using a good light If you see traces of oil or liquid on one of the harnesses in the SAM, that will be ATF. It will have been wicked up from the 13-pin connector on the lower left rear corner of the back of the transmission. This ATF will also be inside the TCU. Follow the harness down, and pull the attached small black plastic box out of the SAM. Carefully open the box and use brake cleaner spray or a similar solvent to completely clean the printed circuit board (PCB) inside the TCU. After it is clean and dry, reinstall it, and see if that helped the problem. It is a good idea to change the connector sometime in the future, as the TCU will be contaminated again if you don't. Incidentally, you can get the connector from any Dodge dealership - the Sprinter uses the same one.
Examine the wire harnesses inside the SAM carefully, using a good light If you see traces of oil or liquid on one of the harnesses in the SAM, that will be ATF. It will have been wicked up from the 13-pin connector on the lower left rear corner of the back of the transmission. This ATF will also be inside the TCU. Follow the harness down, and pull the attached small black plastic box out of the SAM. Carefully open the box and use brake cleaner spray or a similar solvent to completely clean the printed circuit board (PCB) inside the TCU. After it is clean and dry, reinstall it, and see if that helped the problem. It is a good idea to change the connector sometime in the future, as the TCU will be contaminated again if you don't. Incidentally, you can get the connector from any Dodge dealership - the Sprinter uses the same one.
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Joined: Apr 2019
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From: Houston
001 s600, 94 sl600
IMHO you should do the following:
1) Clean out/inspect the cowl water drains to make absolutely certain water is not building up due to plugged drains. IF in doubt, look thoroughly for any signs of water intrusion in the electrical cable channel under the passenger side carpet to the back, and especially under the rear seat. Plugged cowl drains and water overflow into the car can 'brick' the car to a total loss.
2) Inspect the TCU module as described in the previous response. Be cure and use ONLY electrical cleaner, NOT carb cleaner. IF any oil is found up there, be sure and flush the cable bundle down toward the leaking plug on the transmission---and quickly replace that $20 part before it causes you $1000's of grief.
3) IF the TCU is dry/clean, AND there is not water getting into the car, then the 'conductor plate' in the transmission is a known failure item. Have a qualified MBZ shop diagnose to confirm connector plate failure. Replacements are around $300 and shop labor should not exceed an hour. Also replace the transmission filter and pan gasket when the transmission pan is removed to change the connector plate. Total job---replacing the leaking connector plug, pan gasket, connector plate and transmission fluid is not too costly--$20 for leaking plug, $15 trans pan gasket, $300 connector plate, $100 transmission fluid +1.5 hr shop labor. +/- $600
1) Clean out/inspect the cowl water drains to make absolutely certain water is not building up due to plugged drains. IF in doubt, look thoroughly for any signs of water intrusion in the electrical cable channel under the passenger side carpet to the back, and especially under the rear seat. Plugged cowl drains and water overflow into the car can 'brick' the car to a total loss.
2) Inspect the TCU module as described in the previous response. Be cure and use ONLY electrical cleaner, NOT carb cleaner. IF any oil is found up there, be sure and flush the cable bundle down toward the leaking plug on the transmission---and quickly replace that $20 part before it causes you $1000's of grief.
3) IF the TCU is dry/clean, AND there is not water getting into the car, then the 'conductor plate' in the transmission is a known failure item. Have a qualified MBZ shop diagnose to confirm connector plate failure. Replacements are around $300 and shop labor should not exceed an hour. Also replace the transmission filter and pan gasket when the transmission pan is removed to change the connector plate. Total job---replacing the leaking connector plug, pan gasket, connector plate and transmission fluid is not too costly--$20 for leaking plug, $15 trans pan gasket, $300 connector plate, $100 transmission fluid +1.5 hr shop labor. +/- $600
