N55 Valvetronic Relearn
came in with no start, multiple valvetronic codes, found stuck in minimum lift position. replaced valvetronic motor and tried to run adaptation. defaults to minimum lift position and will not run adaptation. engine will not start unless manually move eccentric shaft. using launch and autologic it will not let me adapt. sent dme off for repair and was told circuits were good not sure what I am missing thanks for your time
Ista will relearn it. Unfortunately Autologic had a bug in it. The one work around is to reflash the DME then it will relearn. Did you also change the eccentric shaft and bearings as well? Not sure the DME rebuilder can check the circuits if you have a scope we have a test for valvetronic drivers
Did not change shaft or bearings. Will you feel it binding or is it that sensitive
Its pretty sensitive but as I mentioned Autologic does not run the full relearn in my experience the workaround has been programming the DME. I generally use ISTA on BMW's When you run the test plan with ISTA it states to replace them we have also had bearing bind and cause issues. I am in process of filming a video on this for our website
Here is fault code info gives insight to how sensitive this is
Is it failing on adaptation run as binding? I have replaced several eccentric shafts from binding. Also check IVM which sends powers out to motor and most other electronics on engine. Have put several IVM's in also.
May want to start at relay and check power and grounds there ran into a few faulty relays
Eccentric shaft and bearings pretty well a given at time of motor replacement. Make sure proper lubricant is used on bearings any sort of drag will cause the adaptation to fail.
This is a shaft with wear on it fail to replace will cause motor to often not relearn I have also attached a picture of a failed DME final driver for the three phase
Never had a problem relearning with Autologic probably something binding.
Depends on the state I have seen it about 30-40 times this year on tech support.
Hey buddy, that's my photo! :D Brad, the vehicle in Seth's photo received a new shaft, all 6 bearings, oil nozzle, and valvetronic motor. The shaft did not have any binding bearings, the only wear was on the worm gear and eccentric gear.
Not the DME one, we haven't had one that bad roll through yet.
We have replaced the valvetronic motors and sometimes the DME needs to be replaced also. Autologic has always worked to relearn in our experience. I'm not sure I would trust the DME rebuilder unless they actually loaded those driver circuits the same way they would be loaded on the car. We haven't had to replace the shaft or bearings on any of the ones we have done. These are just the…
I was told the way the dealer diags these issues is by having a N20 head on a roll cart with the cam assembly and valvetronic motor still installed, plugging in the connectors for the motor and eccentric shaft sensors from the car with the fault into the n20 "Test" head and performing the relearn. if it relearns you know the DME is good. I doubt many people have an n20 head laying around.
That is true!! I also have a test with a scope that'd proves in in less than 5 min. Spent 10 hours development on it. I teach it in most classes
Seth I had stumbled upon your website a few months ago.... very much liked what i saw from the training videos on your website. I'm on the watch for one of your classes. You mentioned you have a test using a scope... I'm sure you wont say on here haha ,BUT I recall from a BMW class that you can use a amp clamp and see very hashy 3 phase ramps on a scope but you can not see a voltage pattern on a…
You can definitely see it on a scope,I'll try to work on a write-up not only can you see it but you can prove what's good and bad. I have alot of time and money into this but helps solve a major issue like this
Did you ever finish this write up for checking it with a scope? When I turn my ignition on it tries to do the sweep but looks like it’s binding up. Going to replace the eccentric shaft but wanted to make sure it wasn’t the DME. When I use ista to relearn it tells me engine is not a 0 or it’s in failsafe mode.
Did you ever find a solution for it telling you the engine is not at 0? I'm currently dealing with the same issue.
yes. I ended up having to replace the eccentric shaft along with the motor. Eccentric ended up having minor wear although I was able to calibrate it a couple of times. Don’t forget you can calibrate it without the valve cover on. Just make sure you disconnect the fuel pump of course .
Brad, There is a "circuit breaker" the DME uses which will block movement of the VVT. If this circuit breaker is on, the VVT relearn will fail with the Autologic. You have to program the DME, and do not cycle the ignition at the end of programming. Move along to the VVT relearn function and it will again tell you to cycle the ignition and let the DME main relay drop out. Ignore this and run the…
Maybe not a question for here but when will that be fixed? ISTA resets without the risk of programing. No sure who keeps attacking all my posts.
Hi Brad, As others mentioned, no issues running through this with Autologic. To my knowledge so far, everything has to be just right for this to be accepted. It will run mostly fine if there is a minor issue or something similar, while driven, and will have flexible tolerance limits. BUT, when it comes to relearn, the DME has very low tolerance limits. The DME during relearn is after the most…
Brad- Food for thought: Ive replaced 3 failed PCMs(other makes) that "rebuilders" claimed were perfectly fine and sent back to us. Fortunately my SAs take my word over that of a "rebuilder" and ordered new PCMs anyway.
Sorry for delay. Holidays are tough. In process of programming used dme. Let you know results
Used DMEs will not work without extensive work
Thanks again for all your guidance. Finally this is repaired, I sent dme to be repaired and checked, they said it was good. it was not. I bought a used dme, it relearned valvetronic and made motor move full sweep but would not allow car to start, as expected. Sent dme to a programmer in Florida, he cleared theft and vin info, car started, everything learned, but would not allow trans operation…
So is there a way to verify if the DME has been damaged prior to replacing motor and shaft? We have done a few motors/shafts but not ran into an issues with the DME yet. Just want to make sure we are testing everything we can/should before we tear into one.