SL55/63/65/R230 AMG: SL55 Transmission problems
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Joined: Sep 2013
Posts: 14
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2005 SL55
SL55 Transmission problems
Did a bit of searching around this forum and found a lot of different proposals for fixing my issue. I'm not doing the work myself, but want to have a better understanding of what's going on, would like good advice for what to do next..
Car: 2005 SL55
Transmission no: 2302700700 - 722.643 0 - 5433032
Error code: P220A (comparasion of revs not possible - ish)
Problem is, driving (especially pushing the gearbox) it suddently lock in 2nd gear and refuse to change. Have also experienced it just selecting neutral even though display still shows "S". When problem occurs, I'm not able to select between Sport, Comfort, Manual - neither does it react pulling the leaver to "N" and back to "D" - unless i park, then it selects 2nd gear. Turning car off and turning on again removes problem.
What we've done:
1) Cleaned the plug to the ECU (behind glovebox), was a little wet from some low density oily fluid?
2) Cleaned the plug to the gear box, big plug with like 9-12 plugs in it.. Very oily, but guess that's normal since it's inside the gearbox?
Possible solutions from forum:
1) Replace conductor plate
2) Check oil fluid (had it changed 5000 miles ago, never had any problems, and seems no leaking of gear oil, so maybe unlikely?)
3) Replace transmission.
4) Other?
Any thoughts that might help me decide what to do next?
Car: 2005 SL55
Transmission no: 2302700700 - 722.643 0 - 5433032
Error code: P220A (comparasion of revs not possible - ish)
Problem is, driving (especially pushing the gearbox) it suddently lock in 2nd gear and refuse to change. Have also experienced it just selecting neutral even though display still shows "S". When problem occurs, I'm not able to select between Sport, Comfort, Manual - neither does it react pulling the leaver to "N" and back to "D" - unless i park, then it selects 2nd gear. Turning car off and turning on again removes problem.
What we've done:
1) Cleaned the plug to the ECU (behind glovebox), was a little wet from some low density oily fluid?
2) Cleaned the plug to the gear box, big plug with like 9-12 plugs in it.. Very oily, but guess that's normal since it's inside the gearbox?
Possible solutions from forum:
1) Replace conductor plate
2) Check oil fluid (had it changed 5000 miles ago, never had any problems, and seems no leaking of gear oil, so maybe unlikely?)
3) Replace transmission.
4) Other?
Any thoughts that might help me decide what to do next?
Last edited by MattiasPoul; Aug 7, 2014 at 09:55 AM.
MBWorld Fanatic!
Joined: May 2009
Posts: 1,187
Likes: 239
From: Santa Clara, Ca
2003 SL55 / 2002 SLK32
Did a bit of searching around this forum and found a lot of different proposals for fixing my issue. I'm not doing the work myself, but want to have a better understanding of what's going on, would like good advice for what to do next..
Car: 2005 SL55
Transmission no: 2302700700 - 722.643 0 - 5433032
Error code: P220A (comparasion of revs not possible - ish)
Problem is, driving (especially pushing the gearbox) it suddently lock in 2nd gear and refuse to change. Have also experienced it just selecting neutral even though display still shows "S". When problem occurs, I'm not able to select between Sport, Comfort, Manual - neither does it react pulling the leaver to "N" and back to "D" - unless i park, then it selects 2nd gear. Turning car off and turning on again removes problem.
What we've done:
1) Cleaned the plug to the ECU (behind glovebox), was a little wet from some low density oily fluid?
2) Cleaned the plug to the gear box, big plug with like 9-12 plugs in it.. Very oily, but guess that's normal since it's inside the gearbox?
Possible solutions from forum:
1) Replace conductor plate
2) Check oil fluid (had it changed 5000 miles ago, never had any problems, and seems no leaking of gear oil, so maybe unlikely?)
3) Replace transmission.
4) Other?
Any thoughts that might help me decide what to do next?
Car: 2005 SL55
Transmission no: 2302700700 - 722.643 0 - 5433032
Error code: P220A (comparasion of revs not possible - ish)
Problem is, driving (especially pushing the gearbox) it suddently lock in 2nd gear and refuse to change. Have also experienced it just selecting neutral even though display still shows "S". When problem occurs, I'm not able to select between Sport, Comfort, Manual - neither does it react pulling the leaver to "N" and back to "D" - unless i park, then it selects 2nd gear. Turning car off and turning on again removes problem.
What we've done:
1) Cleaned the plug to the ECU (behind glovebox), was a little wet from some low density oily fluid?
2) Cleaned the plug to the gear box, big plug with like 9-12 plugs in it.. Very oily, but guess that's normal since it's inside the gearbox?
Possible solutions from forum:
1) Replace conductor plate
2) Check oil fluid (had it changed 5000 miles ago, never had any problems, and seems no leaking of gear oil, so maybe unlikely?)
3) Replace transmission.
4) Other?
Any thoughts that might help me decide what to do next?
I would definitely try solving the problem in this order.
1)replace plug adapter and clean fluid out of TCU (contact cleaner should be fine) and retest
note: there is no simple way to remove fluid from harness, but if you cut off the source (by replacing seal at transmission) it should no longer be forced into the TCU. I would also suggest that you rotate the TCU in it's mount (-90°) so that it is pointing down so if your seal fails again (or if you are concerned about residual fluid in the wires) nothing further will make it past the connector of the TCU
(below are a few pics of the TCU remounted)
if problem persists,
2) swap in known good TCU and retest
hope that helps,
Chris
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Joined: Sep 2013
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2005 SL55
Replaced plug adapter, cleaned TCU (also the print card itself had a tiny bit of oil on it) and hope problem is solved. If not, will try to replace TCU.
Thank you very much for your help, now I just gotta do some test driving
Edit: By the way, had the tester connected to the car again today. Got two new error codes I haven't seen before (these are created before cleaning TCU and before exchanging plug adapter).
P2500, P2069
Last edited by MattiasPoul; Aug 8, 2014 at 05:26 AM.
Thread Starter
Newbie
Joined: Sep 2013
Posts: 14
Likes: 0
2005 SL55
Problem is not yet solved, I was able to reproduce "lock in 2nd gear" problem earlier. MB workshop said it might be a better idea to start changing some electric printed circuit inside the gearbox, unfortunately didn't get the part no but we'll try that monday morning.
He strongly refused the TCU could cause this problem, so I wonder.... Anyway, this other fix is cheaper (they charge 1500US$ for a new ECU including taxes here in Denmark..) so we'll go with the cheaper option first I believe.
Will watch the videos later, thanks for that recommendation.
He strongly refused the TCU could cause this problem, so I wonder.... Anyway, this other fix is cheaper (they charge 1500US$ for a new ECU including taxes here in Denmark..) so we'll go with the cheaper option first I believe.
Will watch the videos later, thanks for that recommendation.
MBWorld Fanatic!
Joined: May 2009
Posts: 1,187
Likes: 239
From: Santa Clara, Ca
2003 SL55 / 2002 SLK32
Your mechanic is referring to the conductor plate ...
the TCU 0345451032 is $750 new (oediscountparts.com) and closer to 100 used ... to be clear, when I said "swap in" I meant swap in a known good one .... not necessarily buy it ... of course sometimes you don't get a choice .
the conductor plate should be close to $150 new ... and seems like a reasonable thing to replace
Chris
the TCU 0345451032 is $750 new (oediscountparts.com) and closer to 100 used ... to be clear, when I said "swap in" I meant swap in a known good one .... not necessarily buy it ... of course sometimes you don't get a choice .
the conductor plate should be close to $150 new ... and seems like a reasonable thing to replace
Chris
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MBWorld Fanatic!
Joined: Feb 2009
Posts: 6,897
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From: Central WI (BFE)
SL55, ML500 & Acura TL
It sounds like your problem is solved. Glad to hear it. I will be doing a tranny fluid change this fall before putting my SL to bed for the winter. I am seriously considering replacing the conductor plate and plug while I have the pan off.
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Thread Starter
Newbie
Joined: Sep 2013
Posts: 14
Likes: 0
2005 SL55
MBWorld Fanatic!
Joined: Feb 2009
Posts: 6,897
Likes: 85
From: Central WI (BFE)
SL55, ML500 & Acura TL
Local dealer actually said when I bought the spare part, that whenever they service this gearbox they always recommend to change the conducter plate "while we're in there anyway". Have driven enough miles since to say this problem is completely solved. I'm definitely one happy SL55 owner
