Transmission sequentronic - WONT SHIFT GEARS!
01-16-2011, 04:05 PM
#101
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Thanks Кaro, I did what I wrote in the instructions, but again the error goes to low pressure, I took a friend of a hydraulic pump that works for sure. in this error STAR wrote to replace the pump, it did, the other component B56 pressure sensor ... Tomorrow I order it and change it ... Unseen what else I can already do almost everything I've disassembled, examined, cleaned or whatever is needed .. .. . .. ..
01-16-2011, 05:02 PM
#102
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vakity - I think there is little doubt that our problem is hydraulic. Maybe pump wear or just air. From what Karo has posted it is not clear to me how we get all air out of hydraulic system. Maybe the system is designed to automotically get air out by repeated gear changes manually but it is not well explained in pdf's from WIS.
Karo - can you see if there is anything in WIS that explains how to change & replenish the hydraulic fluid.
Karo - can you see if there is anything in WIS that explains how to change & replenish the hydraulic fluid.
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i.timchenko (02-27-2023)
01-16-2011, 07:25 PM
#104
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Transmission does not shift
Here you go gentlemen. Check out this PDF.
"Transmission does not shift"
Glyn, these are the only documents that WIS has on the SEQ.
"Transmission does not shift"
Glyn, these are the only documents that WIS has on the SEQ.
Last edited by W203E35; 02-07-2011 at 10:33 AM.
01-16-2011, 07:41 PM
#105
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Thanks Karo - I think vakity has found at least one bleed nipple. One should keep the fluid reservior full and you have to get all of the air out of any closed hydraulic system for it to function properly.
I would have expected an air bleed method in "Remove/install hydraulic unit"
Hmm! - from that last pdf. of yours looks like the pump relay is inclined to fail. If it failed the pump would not work. From what vakity explains the pump is working but the pressure is low. This should be air or a worn pump with excessive internal leakage. It might be the pressure sensor sending nonsense to the TCU.
Last edited by Glyn M Ruck; 01-16-2011 at 07:52 PM.
01-16-2011, 08:41 PM
#106
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Yes - That looks like a bleed nipple
Thanks Karo - I think vakity has found at least one bleed nipple. One should keep the fluid reservior full and you have to get all of the air out of any closed hydraulic system for it to function properly.
I would have expected an air bleed method in "Remove/install hydraulic unit"
Hmm! - from that last pdf. of yours looks like the pump relay is inclined to fail. If it failed the pump would not work. From what vakity explains the pump is working but the pressure is low. This should be air or a worn pump with excessive internal leakage. It might be the pressure sensor sending nonsense to the TCU.
Thanks Karo - I think vakity has found at least one bleed nipple. One should keep the fluid reservior full and you have to get all of the air out of any closed hydraulic system for it to function properly.
I would have expected an air bleed method in "Remove/install hydraulic unit"
Hmm! - from that last pdf. of yours looks like the pump relay is inclined to fail. If it failed the pump would not work. From what vakity explains the pump is working but the pressure is low. This should be air or a worn pump with excessive internal leakage. It might be the pressure sensor sending nonsense to the TCU.
01-18-2011, 05:48 PM
#107
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vakity - how are you doing?
We have another similar problem - I think we should all work together to solve.
https://mbworld.org/forums/c-class-w...-workshop.html
We have another similar problem - I think we should all work together to solve.
https://mbworld.org/forums/c-class-w...-workshop.html
01-19-2011, 05:22 AM
#109
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I ordered the battery and pressure sensor, told me that running kit. Waiting for them to arrive from Germany by the end of the week, otherwise they cost here for me is around 200 Euro. I hope that these problems be solved.
Glyn, I saw the topic seems to be the same problem.
See something interesting on the exit of air:
Glyn, I saw the topic seems to be the same problem.
See something interesting on the exit of air:
Vaki
I bled mine prior to installation by sucking oil into the piston chamber by expanding the release bearing assembly and then pushing the remaining air out through the oil line by pushing the assembly back again. I did this procedure several times until no more air was visible. When the gearbox was back in but before the tailshaft was reconnected I then started the engine, put the transmission into 1st gear to make sure hydraulic pressure was applied to the release bearing and cracked the bleed nipple to expel any remaining air. When cracking the bleed nipple, fluid rushed out and the engine immediately stalled due to detecting out of range values so I performed this again being careful not to open the bleed screw too much. Really its just like bleeding your brakes.
Cheers, Iggy66
I bled mine prior to installation by sucking oil into the piston chamber by expanding the release bearing assembly and then pushing the remaining air out through the oil line by pushing the assembly back again. I did this procedure several times until no more air was visible. When the gearbox was back in but before the tailshaft was reconnected I then started the engine, put the transmission into 1st gear to make sure hydraulic pressure was applied to the release bearing and cracked the bleed nipple to expel any remaining air. When cracking the bleed nipple, fluid rushed out and the engine immediately stalled due to detecting out of range values so I performed this again being careful not to open the bleed screw too much. Really its just like bleeding your brakes.
Cheers, Iggy66
Last edited by vakity; 01-19-2011 at 05:27 AM.
01-19-2011, 05:49 AM
#110
Super Moderator
Yes - it is very like bleeding brakes. We will wait for your parts to arrive.
01-19-2011, 06:18 AM
#111
Super Moderator
See other thread
"Ah! another edit - That hose goes back to the valve body so it's part of the hydraulic pressure system & not an air vent. So the pressure reservoir must have a pressure valve in it that vents hydraulic fluid back into the pump circuit. Failure of that valve would PREVENT PRESSURE BUILDUP! We might have to replace the pressure reservoir!"
"Ah! another edit - That hose goes back to the valve body so it's part of the hydraulic pressure system & not an air vent. So the pressure reservoir must have a pressure valve in it that vents hydraulic fluid back into the pump circuit. Failure of that valve would PREVENT PRESSURE BUILDUP! We might have to replace the pressure reservoir!"
Last edited by Glyn M Ruck; 01-19-2011 at 06:25 AM.
01-19-2011, 08:20 AM
#115
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Great - I will try & work my way though that & see what I can understand. Cutaway of pressure accumulator!!! is there.
01-21-2011, 03:14 PM
#117
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What did you do? - change sensor & bleed hydraulics????? Then set up with Star?
01-22-2011, 03:31 AM
#118
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Changed the battery and the pressure sensor, which was not very easy to remove without gearbox but it did. Then run STAR and learn them. Everything went absolutely without any problem. Just do not understand the battery or the sensor was the problem. Thanks guys!
01-22-2011, 06:12 AM
#119
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I'm pleased for you Must be sensor sending bad information to TCU.
How did you make sure that there was no air in the hydraulics?
Anyway - now you know you have a good gearbox.
Must be sensor sending bad information to TCU.How did you make sure that there was no air in the hydraulics?
Anyway - now you know you have a good gearbox.
01-24-2011, 02:58 PM
#120
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Yeah right now I've got really a good gearbox. Tomorrow I expect to arrive hydraulic oil / Pentosin CHF 11S /'ll spew and bled the system. And I hope to have no more trouble with it! 
01-24-2011, 06:36 PM
#122
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01-24-2011, 06:45 PM
#123
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01-27-2011, 01:08 PM
#125
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Let's see, you are +10 hours ahead of me, which means it's about 2am where you're at. I think you be hittin' the wine bottle yo-sef son.
By the way, had nice bottle last night with dinner.
2006 Stonestreet Legacy. The restaurant had a special for 20 bucks.
I just had a feeling about it, was pretty sure I'd heard of it, but not sure where.
85% cab + some other stuff, that a good sign...
Turns out it's a $85 bottle. They totally screwed up.
We're not complaining. It was excellent.
I used a restaurant.com coupon, we had lobster and a nice ribeye with
blue cheese and pancetta, and got out the door for $85 including tax and tip.
Not easy to do these days.
http://www.stonestreetwines.com/wine...cy/legacy.aspx
By the way, had nice bottle last night with dinner.
2006 Stonestreet Legacy. The restaurant had a special for 20 bucks.
I just had a feeling about it, was pretty sure I'd heard of it, but not sure where.
85% cab + some other stuff, that a good sign...
Turns out it's a $85 bottle. They totally screwed up.
We're not complaining. It was excellent.
I used a restaurant.com coupon, we had lobster and a nice ribeye with
blue cheese and pancetta, and got out the door for $85 including tax and tip.
Not easy to do these days.
http://www.stonestreetwines.com/wine...cy/legacy.aspx
Last edited by C230 Sport Coup; 01-27-2011 at 01:18 PM.
