Transmission stuck in 2nd
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Transmission stuck in 2nd
1st post so be gentle. Looking at purchasing a 2002 C180 that has an Auto trans problem. I have read the codes and have P2502 and P220A. Checked TCU plug had some oil but minor cleaned plug and reset but codes reappeared. Checked TCU for wicking but all clear. As I have not purchased the car yet I have not done anything major. Trans is a 722.615 am I able to replace it with any of the 722.6xx transmissions? Radiator is the Valeo A203 500 303 so would be replacing that also. Car is Rhd as I am in Australia if that makes any difference. Thanks for any advice and if someone has a contact for parts that would be great. Cheers Jason
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
The car is in limp mode. The 220A code means that the TCU found that the ouput of turbine speed sensors is implausible.
Usually means you require to fit a new conductor plate to the transmission valve body on a 722.6 ~ not too expensive.
Usually means you require to fit a new conductor plate to the transmission valve body on a 722.6 ~ not too expensive.
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Thanks. Yes I searched a lot before posting the question and was leaning towards that but was not confident after reading how some had been replaced and still have problems. Would there be more codes if there was more issues/damage? I did not extract the codes via a Star machine. I was also concerned about the Valeo radiator because I believe the part number to be one of the affected type. I would rather spend $1500au on a used transmission with warranty than go through the process of replacing the plate only to find it didn't work. Where the car is parked there's a large oil stain on the concrete and a 5lt bottle of trans fluid in the boot so it's been leaking for a while and may have been run very low and caused damage. Are all the 722.6 transmissions interchangeable? Thanks again
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Most OBDII scanners cannot read all of Benz transmission codes. You need a Star for that. I can't sensibly advise you on repair vs replace with used. Both have potential unforeseen problems.
722.6 transmissions are interchangeable. Make sure from another C Class as their are 2 different sets of ratios available. Try & get a post 2003 tranny with TCU. The 2002 TCU's were not reflashable so you could not run the latest software. You will need a Star to adapt the new transmission to the car.
I would replace the Valeo radiator with a Behr. I would replace the electrohydraulic bush with a new one. They are a $10 part.
722.6 transmissions are interchangeable. Make sure from another C Class as their are 2 different sets of ratios available. Try & get a post 2003 tranny with TCU. The 2002 TCU's were not reflashable so you could not run the latest software. You will need a Star to adapt the new transmission to the car.
I would replace the Valeo radiator with a Behr. I would replace the electrohydraulic bush with a new one. They are a $10 part.
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Thank you again. Yes I know it's the question of repair or replace. So if I was to get another trans I would need the TCU also? Is it then a matter of having it adapted to the vehicle or just a clean swap? Our scan tool does have an adaption function in the Mercedes menu but because I've never worked on Mercedes before I don't know what it will do. I can read pressures and other functions with the scanner if that would help with diagnosis. Are the ebay conductor plates that are Mercedes marked the OE item? They seem quite cheap and are all the 722.6 plates the same?
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
It is more ideal to get a newer TCU although you don't have to. The 722.6 behaves far better with the latest flash. The adaption required other than ensuring all lockup pressures are in spec etc. is to make the car recognise the new transmission or it will stay in limp. It all needs to talk to the ECU etc. right up to the EIS which is top of the control pyramid. With a 722.9 things get a lot more complicated because each valve body is individually flowbenched & the calibration data has to be cross flashed to the new EPROM on the conductor plate (integral TCU)
Full Adaption is only possible with Star & Snap On Solus to my knowledge. I am only au fait with Star.
Conductor plates on eBay are usually OE. I don't know of any pirate units but if they exist I would not touch one. Only OE.
To my knowledge every 722.6 conductor plate manuf. from approx 1999 are the same other than quality improvement. Only the TCU changed to flashable & there have been numerous software updates. None recently as the 722.6 is a mature transmission & now only used on diesels.
Full Adaption is only possible with Star & Snap On Solus to my knowledge. I am only au fait with Star.
Conductor plates on eBay are usually OE. I don't know of any pirate units but if they exist I would not touch one. Only OE.
To my knowledge every 722.6 conductor plate manuf. from approx 1999 are the same other than quality improvement. Only the TCU changed to flashable & there have been numerous software updates. None recently as the 722.6 is a mature transmission & now only used on diesels.
Last edited by Glyn M Ruck; May 6, 2013 at 08:54 AM.
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