[BKinNW]

I've been working on an error for low voltage to the valvetronic motor. In short I have replaced the motor, I replaced the battery (and registered it to the car), checked the relay and fuse for the valvetronic motor, checked all of the wiring and everything seems fine. I am getting voltage everywhere I would expect to. I have sent the signal from computer to perform the limit reset for the motor and it states that it completes successfully yet nothing actually happens. The last thought I have is that something is going on with the DME itself. I'm not getting any other errors regarding the DME or other systems though. Any ideas?

I currently only have the diagnostic part of the Pro Tools app on my phone from BimmerGeeks. If I need other software or need to involve a laptop let me know. Thanks in advance.

[DaanBMW]

What do you expect the reset of the VVT motor to do? It's justs a simple "forget the end points" and next time you put your fob in, just do a system on w/o starting the engine (press Start w/o pressing clutch). You will hear the VVT motor go to 1 end, then the other, and that's the relearning of the end stops. If you do not do the VVT motor relearn as described, your dash will turn into a xmas tree. (Ask me how I know...). That's pretty much it.

[BKinNW]

Originally Posted by DaanBMW

What do you expect the reset of the VVT motor to do? It's justs a simple "forget the end points" and next time you put your fob in, just do a system on w/o starting the engine (press Start w/o pressing clutch). You will hear the VVT motor go to 1 end, then the other, and that's the relearning of the end stops. If you do not do the VVT motor relearn as described, your dash will turn into a xmas tree. (Ask me how I know...). That's pretty much it.

I've tried relearning the end points in so many different ways mentioned in this forum and other places on the internet. It's not that it's doing it incorrectly, it's that there is no electricity getting to the motor in the first place. I think it has something to do with the DME not sending the signal and I've ruled out the other electrical issues it may be. But I can't find any other reason why the DME wouldn't be functioning properly.

I have also taken the wiring harness off the DME to look at the contacts for the VVT wires. Nothing seems to be out of the ordinary. No corrosion or anything.

[DaanBMW]

So you're saying plugging and unplugging the VVT motor work the same? assumed you've tried that. that "I am getting voltage everywhere I would expect to" I thought meant you do get the electricity needed at the motor.

also - are you sure you did indeed reset the VVT? if after a reset it doesn't relearn the stops believe me your car will be undriveable. something else to confirm I guess

[BKinNW]

Plugging in and unplugging the VVT motor works the same. No power to the motor at all. I don't think any messages are getting to the motor so I don't think it was reset at any time.

I manually moved the VVT motor to open the cam shaft so the engine would turn over. Other than that the motor isn't moving at all. Just to reiterate, it is a new motor.

And yes, the car is undriveable. It will idle but no power when throttle is depressed. I think that's what I've seen referred to as limp mode.

[DaanBMW]

The car w/ VVT disconnected can still be driven. Power delivery is not similar to when VVT is connected, it's really a lazy drive, but it's still driveable. Can your car still do that?

If connected or disconnected VVT work that same, then your VVT is def not working, but as to why it's hard to diagnose online. It sounded like you measured voltages. Do you get the proper voltage to the VVT?

Again just a simple accessories on (manual gearbox = keyfob in, press Start w/o pressing clutch) will audibly get the VVT to relearn the 2 stops. If a VVT reset was performed, until you do that your while car will work like a demon possessed its soul (I thought I completely FUBAR'ed my car, period).

If it is indeed an electrical issue, I'm as useless as it gets.

[BKinNW]

The car is not driveable as it is. Driving it is like idling plus a little when depressing the gas pedal.

There was no voltage to the VVT. I checked connectivity (Ohms) of the wire from the DME to the harness and it's good. But no voltage even when activating the relearn process with the coding app.

The car is an automatic transmission so no clutch to depress when starting.

[DaanBMW]

I believe for automatics it's w/o pressing the brake pedal.

Not sure what to say - but w/ VVT disconnected the car should still be driveable. I *think* it switches from intake control via the valvetronic (VVT & vanos) to throttle. You might to investigate that as it sounds to me like more than just the VVT is not responsive.

[BKinNW]

Originally Posted by DaanBMW

I believe for automatics it's w/o pressing the brake pedal.

Not sure what to say - but w/ VVT disconnected the car should still be driveable. I *think* it switches from intake control via the valvetronic (VVT & vanos) to throttle. You might to investigate that as it sounds to me like more than just the VVT is not responsive.

The only codes I'm getting are 2A3F and 2A38, which are both Valvetronic related. I would think I would get a vanos related code if there was an issue there.
I'm also getting 2F0D which is Radiator Blind Fault, which my car isn't equipped with.

This is why I don't think it's the VVT and more likely the DME not sending signal to the VVT.

I've downloaded and set up Standard Tools and was thinking about flashing the DME with WinKFP. I'm fairly new to this though and am trying to do as much research as I can before I proceed. Does this even sound like a possible culprit? I think I've ruled out just about every other reason for this.

I've also posted this issue to the BMW Coding section but haven't had any responses.

[Brian86]

Think about it. If the valve lift is at zero no air can get into the combustion chamber. It doesn't matter what the throttle butterfly does. The car will not run.

The whole 'uses the throttle as a backup' thing is predicated on the valvetronic system failing at some intake valve lift value higher than zero. Presumably when the DME detects a valvetronic malfunction it will go into a failsafe mode and try to push the lift to full open then regulate w/ the butterfly.

Perhaps manually turn the motor to raise the valve lift high enough to make the car drivable. Might do something stupid like pegging the rev limiter when you initially start it until the DME figures out there is a problem. I have no idea what combination of valve/throttle the car uses on startup.

If the wires ring out good, and the motor is known good... I don't know what to look at. Broken coupler pins? Bad motor amp in the DME?

[BKinNW]

Yes, I did this. The motor is now set to open and the car starts, but is still in limp mode. I'm pretty sure everything points to the DME. Not sure if its a firmware issue or a hardware issue at this point. Figured I'd flash the DME to see if it works. If not I'll buy a new DME and program it to the car.

Thanks for the reply.

[lowrydr310]

How many miles are on the car, and do you have any record of ever replacing the eccentric shaft sensor? I only ask because I started getting some random valvetronic errors on my 330 shortly after I bought it. I was focused on the valvetronic motor itself because I couldn't get it to move even when commanding it with INPA (and because that's what all my error codes pointed to) however at some point soon after I got a code indicating a bad eccentric shaft sensor. I replaced that, and the car has been running fine since.

I'm not saying this is your problem, just something else to consider before you conclude it's a bad DME. If the sensor is partially failing, the DME doesn't know exactly where the eccentric shaft is positioned.

[BKinNW]

How many miles are on the car, and do you have any record of ever replacing the eccentric shaft sensor? I only ask because I started getting some random valvetronic errors on my 330 shortly after I bought it. I was focused on the valvetronic motor itself because I couldn't get it to move even when commanding it with INPA (and because that's what all my error codes pointed to) however at some point soon after I got a code indicating a bad eccentric shaft sensor. I replaced that, and the car has been running fine since.

I'm not saying this is your problem, just something else to consider before you conclude it's a bad DME. If the sensor is partially failing, the DME doesn't know exactly where the eccentric shaft is positioned.

I've checked the valvetronic system for voltage and nothing is coming from the DME even when told to send the limits reset. I deduced that even if the eccentric shaft sensor was at fault there is still something going on with the DME sending signals.

I know this is a beginner mistake but yesterday I checked the entire car for errors. (Something I thought I was already doing) There are many more errors coming from many of the other modules in the car and they are all pointing back to the DME saying they aren't getting signals. I think this means the DME is bad but I'm going to try to flash it tomorrow. We'll see.