SL-Class (R230) 2003 -- 2012: Discussion on the SL500, SL550, SL600

SL/R230: Transmission Issue

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Old Jul 1, 2018 | 09:11 AM
  #1  
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2003 SL500, 2016 F250, 2017 Jeep Renegade
Transmission Issue

I had left work and pulled over to make cell call for 2 minutes, I than when done moved shifter into drive and nothing car just rev'd as it did in all gears. I also noticed even in Park position I could push the car. I had it towed to dealer as I was to far from home. The attached is dealer video. Curious of any thoughts. I did before they brought it in I went there and attached my SDS and there were no codes.

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Old Jul 1, 2018 | 09:28 AM
  #2  
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From: amarillo texas
2003 sl 500
tranny problem

It looks like they are looking into the tranny fluid wicking up the control wires to the TCM. A headache when the tranny connector seal goes bad. A O ring starts leaking and things go to pot. I cannot see well enough to see if oil is on the wires or not. I guess that may be better than a tranny overhaul job. Keep us posted.

moretech
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Old Jul 1, 2018 | 09:55 AM
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I will, yes it is wicking up the lines, but did not throw any codes when failed, which is weird, I'm hoping it isn't the conductor plate in tranny.
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Old Jul 1, 2018 | 10:50 AM
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Have other folks had this happen?
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Old Jul 1, 2018 | 12:25 PM
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From: amarillo texas
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tranny

Yes! Several reports of this. I got under mine to check all was dry a bit back,
moretech
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Old Jul 1, 2018 | 12:36 PM
  #6  
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From: amarillo texas
2003 sl 500
tranny conductor plate

I notice the conductor plate is $150 on amazon, if you need it, but I think not. Sorry you need the dealer though on this one. I seem to remember from other members comments that the 722.6 tranny is not as difficult a job as the '04 and up 7 spd trannies.

moretech
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Old Jul 1, 2018 | 01:46 PM
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This is a common problem on the 722.6 transmission. The pilot bushing seal on the transmission connector leaks and you'll get a puddle on the garage floor and fluid "wicking" into the TCU. Some DIYers have been able to take the TCU housing apart and clean everything to salvage it. Moretech is correct that the 722.6 is cheaper/easier to repair. The 722.9 TCU is built-into the conductor plate, making that part much more expensive. Plus, the 722.9 TCU is part of the Drive Authorization system, so it requires a bvirgin part and SCN coding by a dealer (or live connection to MBUSA to download the VIN-encoded firmware). The 722.6 doesn't need SCN coding, and since the TCU is external, the conductor place is much less expensive. You can even install used parts for a TCU repair on the 722.6.

I will say I am impressed with this technician's work in giving you that video. All dealerships should be that thorough and customer-focused.
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Old Jul 1, 2018 | 02:23 PM
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From: amarillo texas
2003 sl 500
tranny headaches

Rodney, thanks for jumping in on this one. I knew there were some big headaches on the newer 7 speed trannies. I guess if I ever buy another SL it'll be an even lower mileage '03 than my 45000 mile one (was 35000, 3 years ago). The model year variances can cause some hefty problems for DIY'ers when it becomes a dealer fix or stop driving.

moretech
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Old Jul 1, 2018 | 02:26 PM
  #9  
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Originally Posted by Rudeney
This is a common problem on the 722.6 transmission. The pilot bushing seal on the transmission connector leaks and you'll get a puddle on the garage floor and fluid "wicking" into the TCU. Some DIYers have been able to take the TCU housing apart and clean everything to salvage it. Moretech is correct that the 722.6 is cheaper/easier to repair. The 722.9 TCU is built-into the conductor plate, making that part much more expensive. Plus, the 722.9 TCU is part of the Drive Authorization system, so it requires a bvirgin part and SCN coding by a dealer (or live connection to MBUSA to download the VIN-encoded firmware). The 722.6 doesn't need SCN coding, and since the TCU is external, the conductor place is much less expensive. You can even install used parts for a TCU repair on the 722.6.

I will say I am impressed with this technician's work in giving you that video. All dealerships should be that thorough and customer-focused.
I know Rodney, me and the wife were eatting lunch and I got text message with video link to download, I told them same thing, that is was amazed
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Old Jul 1, 2018 | 02:33 PM
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I don't think TCU went away, simply can open the TCU cover & clean it with contact cleaner,,

done that many times with soaking TCU's..

-;ZAYED;-
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Old Jul 1, 2018 | 10:03 PM
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Originally Posted by cm60k
I don't think TCU went away, simply can open the TCU cover & clean it with contact cleaner,,

done that many times with soaking TCU's..

-;ZAYED;-
The dealer won't do that, though, because officially, that's not a repair procedure and the TCU housing is "sealed" (well, sort of). But that's the great thing about DIYers and Indy shops - they can do these "unofficial" repairs.
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Old Jul 1, 2018 | 10:17 PM
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Originally Posted by moretech
Rodney, thanks for jumping in on this one. I knew there were some big headaches on the newer 7 speed trannies. I guess if I ever buy another SL it'll be an even lower mileage '03 than my 45000 mile one (was 35000, 3 years ago). The model year variances can cause some hefty problems for DIY'ers when it becomes a dealer fix or stop driving.
The 722.9 is really a great transmission, it just had some problems with the early units. Look for a MY2008 or later and it should be beyond all those issues and be as reliable as the 722.6.

Keep in mind that while SCN coding is a pain the butt to deal with, there are other parts that need it, too, like the gearshift module on the SL or the steering column locks on cars that have them (the SL does not). It's MBZ's attempt to keep the cars from being stolen. For example, a thief can't just plug in his own EIS to start the car because the key has to be validated by the ECU and the TCU (and the ESL, and AGS, etc.). Now, what would be great is if they made a way to "unlock all systems" so owners who don't care about the high security and need to DIY repairs. But then again, the bad guys would figure out how to do that and use it to steal cars. Yes, there are "ways" to get around SCN coding, but none of them are cheap or easy enough that a thief would bother.
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Old Jul 2, 2018 | 12:24 PM
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This morning drove to work in my other vehicle and when dealer opened went down to meet Tech. I asked her to check transmission fluid level as with the wicking I may have lost some fluid and if significant could be another reason why its not going into gear. I also asked her to look at linkage as when I moved shifter to any gear the car was still in neutral which she wasn't aware of. Fingers X'd here. She does and I agree that the Plug and TCU need to be repaired as in Video.
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Old Jul 2, 2018 | 01:02 PM
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These kind of issues, not the things that most people not aware of..!,

unfortunate, dealers always want to show you they beat the secret of the issue you came across,

most of dealers, when you come to them, they only thinking how to break your WALLET not to save your car or even respect your value TIME..!!,

If you are vampire or Zombie, just hurry up, dealer will higher you without even interview..,,

watch out your necks fellows..

-;ZAYED;-
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Old Jul 2, 2018 | 05:26 PM
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Ok , so was driving home from work and got call from dealer, they put new parts in Connector and Orings and TCU. But still wouldn't shift. Turns out that it was exactly what I suspected it was, the Linkage Bushing. They were in agreement that I was correct and I also agreed that the parts did need maintenance that they discovered. So they ordered Linkage parts to fix for tomorrow.
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Old Jul 3, 2018 | 12:35 PM
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tranny problem

Cadbob, it bugs me a lot that they did not notice the bushing problem right off. I'd think they'd check that 1st thing with "no shift" at all. oh well, such is life!

moretech
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Old Jul 3, 2018 | 01:06 PM
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Originally Posted by moretech
Cadbob, it bugs me a lot that they did not notice the bushing problem right off.
Not only that, but I presume they needlessly replaced the transmission controller. Where oil has contaminated the controller its functionality can usually be restored by simply removing the oil. That said, I wouldn't fault the dealer in this case, since I presume a standard policy of dealers is not to repair electronics.
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Old Jul 3, 2018 | 07:38 PM
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So home with SL parts 42.00 Labor 447.00 Easy job but I had no choice. I told them put my old TCU back in.

They are a good honest dealer thou like all of the dealers of any make they are Parts re placer's

I told them this morning that my original diagnose was that it was the bushing and i even wrote it on Key envelope dropping car. The next day to confirm in lot with my own SDS that it wasn't software but hardware.
I said i feel like a guy going for filling and coming out with all his teeth out! lol With the original quote including TCU was 1,999.00

Last edited by cadbob; Jul 3, 2018 at 07:42 PM.
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Old Jul 3, 2018 | 08:53 PM
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So did they fix the leaky pilot bushing seal? If not, you need to take care of that. As Bobterry stated, the TCU can be cleaned. To do that, you have to crack it open. That's why dealers won't do it, because the case is glued together not designed to be opened.
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Old Jul 3, 2018 | 10:40 PM
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Yes, I did have them replace the Pilot Bushing and Seals, I told them that much of there diagnose I agreed with. They said the TCU was reading dead no co,communication and tech swore by it, I said well I don't but no fails on my SDS and I would go play lottery with Snapping the Linkage Bushings and Shorting out the TCU at same time! lol So put old one in cause I know I'm a working stiff and no lottery for me!
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Old Jul 4, 2018 | 05:09 PM
  #21  
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Sooooo the small saga continues guy's. The wife and I decide to go for ride after getting back from Mercedes of Springfield yesterday for my Transmission issue.
Well I look down at my gauges and I have the CHECK ENGINE LIGHT on. I'm like damn that is weird and coincidental, but she wasn't running or ideling rough and was thinking they may have tripped a O2 Sensor, so we continue our ride.
I got home and hooked to SDS and have engine codes I never got, especially after checking at dealer lot also before Transmission bushing fix. Attached are the codes. I than removed engine cover and seen the hose by my Mass Airflow sensor unplugged!! See attached.
I'm not sure what the thing is it coming from or going to but would like to know.
Attached Files
File Type: pdf
Codes.pdf (237.3 KB, 143 views)
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Old Jul 4, 2018 | 06:27 PM
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Purge valve, feeds excess fuel vapors into the engine. Plug it back in and clear the codes, then carry on. Probably got pulled off when they removed the airbox to check stuff and didn't notice.
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Old Jul 4, 2018 | 06:59 PM
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Ooooo, gash..!,,

i told you my good friend about those Zombies mistakes..,,

take this photo, and show it to them,

ahhhh, BTW; don't forget to bring some Garlic, throw it on those Zombies,,

you will definitely be soooooooooooooo HAPPY...

-;ZAYED;-
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Old Jul 4, 2018 | 08:19 PM
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Originally Posted by ItalianJoe1
Purge valve, feeds excess fuel vapors into the engine. Plug it back in and clear the codes, then carry on. Probably got pulled off when they removed the airbox to check stuff and didn't notice.
Joe, would that cause those codes?
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Old Jul 4, 2018 | 09:19 PM
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Originally Posted by cadbob
Joe, would that cause those codes?
The giant air leak you have because that line is off. The car is adding fuel to compensate for air coming in after the MAF, and it's too much to be normal, so it sets a code. Plug the line in, clear the codes, and go.
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