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Before coming onto this forum and making yourself look like a fool by writing laughable posts such as that, I'd like you to backup your claims. I'd like you to cite a single time I ignored or dismissed anyone giving me advice. I'd also like to see you cite the many times I repeatedly posted where many other "automotive techs" who attempted to solve this issue had no success. And finally, I'd like to see you find a specific wire out of a 14 wire loom with very limited access on an obscured plug. Here's a picture of that. As soon as you find it, let me know!
If you're just going to come on here to be a nuisance and make yourself look like an idiot, I suggest you do not post here again.
I would not sell a car to someone whose brain has been half-assed and hacked since birth to someone like you.
The purpose of a capacitor is to smooth out voltage going into a circuit. I don't know its exact function in this specific application, but I bet its the same as in any other circuit.
It definitely isn't necessary in this application (hence why the car runs perfectly fine without it), but it is a good idea for safety reasons just in case there was any sudden voltage spikes going through the TCM circuit.
I definitely don't need to replace the TCM or transmission because this little thing broke off - It should be fine for the time being until I find the time to solder in a new capacitor in the near future.
Maybe, there are applications in which this type of capacitor is essential!!
You cannot say that. The absence of this capacitor can create unwanted voltage spikes which can cause seemingly undefinable problems!!
You just don't know. This is an inexpensive item and has the potential of causing unknown problems.
How come it was loose to begin with??
The capacitor was loose the moment I opened the TCM - it may have been broken long before that. And yes, I do agree I need to solder in a new one.
I found this video where the guy explains what it does and how the specific TCM he was working on had a non-functioning capacitor for quite some time but still worked fine.
It was loose inside the Box! Was it attached by one leg? That would make me very suspicious. I spend a lot of my years in circuit design. There is no designer I know of, who places ***** nilly an electrolytic capacitor in any circuit. I personally used them only when absolutely necessary. And when necessary I mean it. They are bulky, have relatively low reliability, limited temperature range and are costly. These parts are mechanically mounted considering the application fairly high G-forces. That implies that unit has been opened before and abused. I cannot see any way that this capacitor broke off during normal operation.
To have such a part rattle around in an module like this can lead to all sorts of problems which will be intermittent.
Anyways I suggest that you give this module a good visual examination, in particular look for scratches and maybe even bad or damaged solder joints. This should be done under a stereo microscope.
Good luck!
Last edited by parker15555; Mar 31, 2020 at 07:40 PM.
It is a surface mounted capacitor, there were no pins going into the motherboard itself which would be more reliable. It's a possibility that it came loose from all the oil saturation over the years since that TCM box was never opened or cleaned before.
When I inspected the TCM all the circuitry looked fine and had minimal corrosion. I cleaned it the best I could, and it's working now in the car flawlessly. I'll have to take it back out to solder in a new capacitor now - better safe than sorry
I know it is a surface mount capacitor!! No, it did not come loose in normal usage!! AND NO, THIS BOARD DOES NOT WORK PERFECT SINCE YOU DON'T KNOW WHAT THAT LOOKS LIKE!!!!!!!!!!!
Last edited by parker15555; Apr 1, 2020 at 07:34 AM.
Alex Mer--- You have been so persistent in attempting to fix your car---why ignore a known defect in a critical computer, especially when the 'fix' is so simple and clear???
You owe it to yourself to replace the capacitor promptly and not risk further damage.
Yes I know I have to go back and fix that, I didn't drive the car too much without that capacitor.
I also want to cut the wire to the TCC solenoid while I'm there, but I cannot figure out which one it is. I know it's on terminal #17 but the plug that goes into the TCM is obscured and you cannot pinpoint where the #17 wire is. You can't take apart the plug either, and I'm not willing to break it open to see which wire it is. The wires are color coded, but I have had no luck trying to find what color wire #17 is online. It's supposed to be black/yellow according to a few 722.6 documents I found online, but none of the wires are black/yellow on my plug.
I finally found the wire for the TCC solenoid from the TCM and cut it.
This revealed 2 things:
-The jerking/hesitation went away
-The car is now in limp mode and won't change gears (CEL is on)
I'm kind of in a pickle here now - the fault detection for the TCC circuit is clearly working, but why does is not throw any fault codes when the wire is connected? There is clearly something wrong with the TCC clutch, since the car works perfectly with it disabled, but it never threw any codes until I cut the wire. It makes no sense. I'm going to reconnect the wire now and try to figure out another way - anyone have any ideas? Will a resistor trick the computer into thinking the TCC wire isn't cut?
In a sister forum, someone reported (yesterday) that the wire is Grey/Black. I know it is of little use now, but just in case you cut the wrong one.
Post 29 in:
Will a resistor fool the TCU into thinking the TCC solenoid is still connected Probably Measure the solenoid resistance to ground (+/- 6 ohms?) and replace with resistor of same resistance---sized to handle the heat. 12 ohms gives 1 AMP current or 12 watts which is the heat it must dissipate.
What does +/- 6 ohms mean?? It is either 6 ohms or not. Assuming it is 6 ohms the current flowing at 12V will be 2 Amps equating 24W. It has to dissipate 24W, Choosing a resistor for such an application is a different story. This depends upon the acceptable temperature rise of the resistor body. My suggestion would be to buy a 50W chassis mounted resistor which would be screwed to some metal surface.
Last edited by parker15555; Apr 15, 2020 at 03:23 PM.
Thank You Mr Parker15555 for explaining what I wrote assuming the reader in this topic would comprehend what I wrote. Most would understand the question mark ? after the nominal resistance indicates I am not certain of the actual resistance, which I have advised the performer to MEASURE, but it SHOULD be around the value I indicated. It will not be 2 OHMS, nor will it be 50 ohms. I erred in not using 4 ohms to illustrate Power (heat to be dissipated) = current squared times resistance.
Sorry Mr. Kebowers47, I did not read your previous post careful enough. The arithmetic is simple enough. The real life problem is how to dissipate the generated heat and not burn up the resistor.
Last edited by parker15555; Apr 15, 2020 at 04:51 PM.
Well it looks like it wasn't the brightest idea going around cutting wires - the car is now stuck in limp home mode. This was the exact fear I had that was preventing me from cutting the wire, but I did it anyways. Nice!
I reconnected the wire but the car is still in limp home mode. There is now a nasty high pitch whining noise coming from the transmission that was never there before - I don't understand how a transmission could be totaled from cutting a single wire...
Hesitation/jerking is completely gone now while stuck in second gear limp home mode. At least I found the problem for sure
I had the TCU completely reset using a scan tool after reconnecting the wire and things are back to normal again. No more whining noise from transmission, and the car shifts just fine. Phew!
Hesitation IS back though! Since cutting the wire was not an option, and I'd rather not mess with resistors in a computer as sensitive as the TCU, there has to be another way.
Is it possible to program the TCU to not lock the torque converter in 1-4th gear with a TCU tune? That way it will lock up in 5th gear on the highway only (like every other normal car) and leave the first 4 gears alone, solving the problem entirely without risking overheating the transmission. I remember watching a youtube video by a guy named legitstreetcars where he talks about doing something like this. He was having similar issues and changing the TCC solenoid/valve didn't really fix his issue, and he brought up the point of programming the lockup function out in the first 4 gears with a tune.
Though I'm a subject matter expert (45+ years) and can easily prove it through my private website, I won't waste my time trying to assist. I stand by everything I say. It's all in the posts. Simple as that. Yeah, it looks like you've really got a handle on this. LOL.
Enjoy your continued struggle, Mr. Nasty! You deserve all of the problems you're going through. Improper diagnosis and randomly chopping wires don't work. Try to wrap your head around that fact.
Originally Posted by AlexMercedes
Mr. "Benz-4-the-win",
Before coming onto this forum and making yourself look like a fool by writing laughable posts such as that, I'd like you to backup your claims. I'd like you to cite a single time I ignored or dismissed anyone giving me advice. I'd also like to see you cite the many times I repeatedly posted where many other "automotive techs" who attempted to solve this issue had no success. And finally, I'd like to see you find a specific wire out of a 14 wire loom with very limited access on an obscured plug. Here's a picture of that. As soon as you find it, let me know!
If you're just going to come on here to be a nuisance and make yourself look like an idiot, I suggest you do not post here again.
I would not sell a car to someone whose brain has been half-assed and hacked since birth to someone like you.
I said it before but looks like I have to say it again - if you're just going to come on here to be a nuisance and make yourself look like an idiot, I suggest you do not post here again. Maybe the Alzheimer's is getting to you!
Considering how old you claim to be, you should be ashamed of yourself to go on the internet and brag about experience that nobody cares about or benefits from, and put others down for no reason. Everybody in this forum has offered nothing but help and support, something I greatly appreciate, and then comes a useless a**hole like you thinking you are better than everyone without proving so or doing anything to contribute to the forum. You should know better than that, especially at your age! It's crazy how pathetic some people in this world could be.
I'm not going to reply to anymore hateful posts like this - I'm going to try to keep this thread as clean as possible until I have found the solution. With that being said, there are some new developments:
I contacted a few tuners, and some have said it is possible to disable the TCC through TCU programming. I'm not sure which exact tuner to go with, so any personal experiences with good tuners you guys may have, please give me your recommendations!
Yeah, I'm close to two-thousand years old. Time for my nap. Keep the psycho-babble to yourself. You look ridiculous, Cupcake. I'm not ashamed of anything and neither are my clients. There's a reason real-life experts don't post advice here.
PS: stop dragging your knuckles. It's easier to walk.
Originally Posted by AlexMercedes
I said it before but looks like I have to say it again - if you're just going to come on here to be a nuisance and make yourself look like an idiot, I suggest you do not post here again. Maybe the Alzheimer's is getting to you!
Considering how old you claim to be, you should be ashamed of yourself to go on the internet and brag about experience that nobody cares about or benefits from, and put others down for no reason. Everybody in this forum has offered nothing but help and support, something I greatly appreciate, and then comes a useless a**hole like you thinking you are better than everyone without proving so or doing anything to contribute to the forum. You should know better than that, especially at your age! It's crazy how pathetic some people in this world could be.
I'm not going to reply to anymore hateful posts like this - I'm going to try to keep this thread as clean as possible until I have found the solution. With that being said, there are some new developments:
I contacted a few tuners, and some have said it is possible to disable the TCC through TCU programming. I'm not sure which exact tuner to go with, so any personal experiences with good tuners you guys may have, please give me your recommendations!
Have you considered changing the solenoid and or the conductor plate, maybe performing an adaption of the tcc afterwards?
Im having the same problem, cant do it becaise of the lockdown.
Those were both changed and adaptations were done, with no result. There could be two things actually wrong here - The valve body has scoring in the bores relating to the lockup valve and needs to be replaced (more likely), or the torque converter has significant wear on the lockup clutch and needs to be replaced (less likely).
I haven't been able to contact any Mercedes parts department to get a price for a new valve body due to the current world situation. The best option for me right now is programming the function out until the covid crisis calms down. Afterwards I will attempt to properly tackle the issue by first trying to replace the valve body with a new unit.
"I haven't been able to contact any Mercedes parts department to get a price for a new valve body due to the current world situation."
Really? I have just contacted the parts departments of every Mercedes Dealership in the Metro Atlanta area and in Chattanooga in order to buy a key for my S500. All were open for business and very helpful. I visited the Chattanooga dealership twice last week the dealership was open for business as usual, and very helpful.
"I haven't been able to contact any Mercedes parts department to get a price for a new valve body due to the current world situation."
Really? I have just contacted the parts departments of every Mercedes Dealership in the Metro Atlanta area and in Chattanooga in order to buy a key for my S500. All were open for business and very helpful. I visited the Chattanooga dealership twice last week the dealership was open for business as usual, and very helpful.
The lockdown is much more strict in LA - pretty much everything is closed here. I usually order parts from Keyes European Mercedes and their parts department is closed until mid May.
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