Marchy63

Have problems with error code P0721, at first everything pointed to the conductor plate that I had to order. When we first installed it, the car did not want to start until we went through the introduction the procedure. the car started and we got in new oil and i drove a lap and the car changed gears perfect.
When I got home I was going to park the car again and then I noticed the same jerk I had before and the car went into limpmode.
The error code P0721 can be deleted so that the car can change but the problem continues to appear, can not say exactly when but it seems like when to start it with cold oil
Any suggestions where the problem may be?
Thanks in advance

roadtalontsi

did you replace it with a new one?

Marchy63

Yes I switched to a virgin device that has been coded for my car but I get the same error code as I had on the previous module but the difference in this case is that the error code can be deleted from the system as it could not be done on previous device. So progress has been made but I do not know why it gets the same error code on the new device again

roadtalontsi

If it's still throwing a turbine speed sensor fault after replacement it's either a bad new part, the valvebody and or transmission is toast causing gear slippage or installation error. The turbine speed sensor is built into the plate.

eightysixtuned

you know i love asking the same question for everything..."are you stock or tuned?"

Marchy63

Its output speed sensor not internal, someone told me I need to delete the error code and make a full adaptation for it to work. have not done so yet. could that be the problem? or faulty software?

Marchy63

installed the new plate and the same error code comes again, the plate was used but I wonder if there are other reasons than just the output speed sensor that may be wrong? I read something about intermediate shaft that can also give rise to signal errors

eightysixtuned

I guess you don't want to answer my initial question as I ask because if a tune i built incorrectly it CAN throw this code.

Marchy63

I unfortunately can not answer whether it is optimized or not because the seller did not know either But I will try to contact any previous owner and ask

GarlicBread

Your computer comes with a CVN number from the factory.

If your CVN has changed = tune. No change = no tune.

Take it to a mercedes dealer, they'll plug it into the witchcraft detector and let you know.

hachiroku

CVN can be included with a tune.

roadtalontsi

So it's a used part? It doesn't sound like you know what you're doing. I'd definitely seek professional assistance.

Marchy63

You can make used parts virgins and encode them adding new wine numbers, so there should be no problem but I definitely have an idea of ​​what I'm doing, but as I said it could be that the part I bought has a bad sensor, but they would send another unit so we'll see if it works

roadtalontsi

You own a C63. If you're resourceful enough to be able to virginize parts you can afford a new replacement. Full retail is like $500. Why would you gamble and waste your time? it's totally different if you have a c250 or c300 with 200k miles on it. Sure play games and save money.

skullbox15

Are these conductor plates easy to get?

Marchy63

you can buy them from retailers but they are quite expensive. But I bought a brand new one now and still have the same problem 😞

roadtalontsi

It's a theft related part (TRP) so it's like a key. They shouldn't sell it to you without proof of ownership, id and vehicle being present in the U.S. That's not to say other places aren't selling them online but they if they get caught by MB things wont fair well for them.


As for the new part not fixing it.... Sounds like it has a mechanical problem not electronic, misdiagnosis.