[manyrin2022]

Hello everyone, there was a problem with the B58 with the error: crankshaft sensor signal:missing.

Car: BMW F30 340xi, Stage 3, VTT GC+, WMI (BMS) + DI (750cc), Reflex (ver. Ecutek 09/2023), Manifold BMS, HPFP TU, LPFP Spool Performance Stage 3 Diy Kit.

Signs of the error:
1) A little worse start than usual; (but actually within the normal range, since it's quite cool outside).
2) Cylinder timming correction when the car is driving (logg bm3);

The coils, spark plugs, injectors, and ventilation valve were immediately checked and replaced, which did not give positive results.

I repeat, there were no crankshaft sensor errors.

Over time (the car was in the service all the time), looking for the problem of why the tim. corrc and poor start of the car appear, it was discovered that the car began to take a very long time to start (by the way, the car was just in the service for several days) and the crankshaft sensor signal:missing error appeared.

The following decisions were made:
1) Replacing the crankshaft sensor, part number 13627806782;
2) Checking the wiring under the hood and in all places where it can go + checking the fuses;
And yes, it didn't work, more than 5 new sensors were used that didn't work and the error remained. Wiring, fuses are all in perfect condition with no signs of damage or anything like that.

During the inspections, it was decided to pay attention to the Motiv Reflex installed on the car (ver. EcuTek 09/2023).
When checking the reflex unit, it was confirmed that the unit itself was working, but in fact there was no signal from the wires from the crankshaft sensor.
There was also a theory that the gearbox had to be dropp to get to the wheel from which the crankshaft sensor was reading vibrations (like the wheel itself was broken and actually wasn't sending a signal to the sensor itself).
But, continuing to search for the problem (in order not to touch the gearbox), after checking the entire car, it was discovered that it was the DME that was not sending a signal to the crankshaft sensor.
Let me remind you that this is a B58 engine and you almost never find such errors online, so you can understand where to look and what to do.
At the moment, the DME is under repair, specifically on the contact that is responsible for powering the crankshaft sensor. I will add to the topic when it returns.

If anyone has had similar problems, please write, I'm curious to know who else has encountered this?

Also, as I communicate with the masters, I will add to this post.

Update:
I received the repair unit, the problem was confirmed, the contact responsible for supplying power to the crankshaft sensor burned out.

So, it remains to try to find out what caused this contact to burn out.

Update:
The DME was installed on the car for several days, no errors appeared.
The car started without reflex for the first few days, the last 2 days it idled with reflex, all wiring, contacts, fuses were checked, nothing was found. The technician said that he did not know what the problem was that caused the DME to burn out, so the search for the problem is over, the problem is solved (by restoring contact in the DME block, which is responsible for powering the crankshaft sensor).

UPDATE 06.01.2026
While driving in normal city mode at low revs, the car started to sputter/stall and after stopping, the following error codes appeared:
1. 213601 - power management: quiescent current violation
2. 20E120 - Suspected leaks in air-carrying components
3. 160021 - Crankshaft sensor: general loss of synchronization
4. 160021 - Crankshaft sensor, signal: missing
5. 21A026 - Combustion engine: abnormal key/MSA start detected (Combustion engine: Abnormal ignition key or automatic engine start-stop function start detected)
6. 6. CF2C25 Signal (crankshaft speed, 0xA5) invalid, transmitter DME/DDE

I recently repaired the DME unit, but the errors returned, now I don't even know what the problem could be.

Update 09.01.2025
new details about the type of error and its symptoms.
If the car was standing at night and it is cold (or during the day it also cooled down) then there is no error and the car starts without problems and for the first 20-30 minutes it generally behaves perfectly.
After 20-30 minutes have passed (I have personally checked it) the car is warmed up and at one point it just starts to stall while driving (a feeling of lack of fuel or a large amount of air) then it continues to drive normally, but if after signs of stalling of the car appear while driving - stop, then the box automatically drops to N and the car stalls, if you try to start it the starter starts to spin for a long time, and errors 160001 and 160021 come out, which will appear all the time even if you erase the errors.
If you let the car stand for a few hours, the error disappears by itself, everything works perfectly for the next 20-30 minutes.

Yesterday, we did a significant amount of work with an electrician and discovered the following:
If the car is cold and you start it at idle for 1 hour, then there will be no error.
If the car is cold and you start it, warm it up and then drive in easy mode for 20-30 minutes, then these errors appear.

The whole difficulty of checking is that you need to disassemble the car each time (but this is not done in 1-2 minutes) to get access to the crankshaft sensor and the wiring that is near it.
Therefore, we quickly found that when an error appears, the reflex receives a very, very weak signal from the crankshaft sensor, but it is there, so we exclude the DME that the problem is in it.
The next step was to remove the reflex (adapter) and connect the factory wiring to the crankshaft sensor, after which the car was used for 2 hours and the problem did not appear, then we returned the reflex (adapter) and so far nothing has happened, we are monitoring the situation, if the error appears again, we plan to completely resolder and replace all the reflex sensor chips that are connected to the crankshaft sensor.

I will also add that the car is used on E20-E25 in winter, the weather outside is very, very humid both during the day and at night, and sometimes there can be frosts down to -10 Fahrenheit. There is a suspicion that the reflex and its wiring are not adapted to such a climate (but these are all just suspicions), since the first symptoms appeared when there was heavy rain outside for 3 weeks without stopping, and the second time when there were strong drops in frost and humidity. I repeat, the Motiv reflex and visconti tuning ignore my messages, I write to them every few weeks and ask for help.

UPDATE 12.01.2026
We connected the factory wiring to the crankshaft sensor connector for 2 hours, then turned the reflex wiring back, the car was used in normal mode for 3 days, there are no errors, I will monitor the situation further

Update 29.01.2026
Hello everyone, the problem has returned.
The symptoms are all the same as before.
On a warm car, driving around the city in normal mode, 1-2 gear, give sharp turns from 1000-1500 to 2000-2500, there is a strong blow, it feels like the engine has stopped and the error p0335 appears. After that, leave the car for a while to cool down and the error disappears, I continue to search for the problem.

Update 04.02.2026
Diagnostics, as usual, did not show anything that would help correct the situation.
As of now, it has been decided:
1) Replace the crankshaft position sensor with a new one (this is the 3rd replacement);
2) Completely replace the wiring that is responsible for reading the crankshaft sensor from the reflex to the chip with the sensor itself;
3) Completely redo the crankshaft sensor chip (reflex)
4) f80paul is in touch and trying to help, for which I respect him, he provided updated firmware reflex (I hope that maybe the reflex itself is buggy)
I will write based on the results whether I managed to resolve the situation.
Maybe it will be useful to someone, update from 03/12/2026
The whole problem was in the wiring harness under the hood, namely the adapters to the Visconti connectors. We cut the wiring harness and connected it directly without the visconti wiring, now everything works
Therefore, Visconti wiring is generally not a good option, be careful if you use it.
Now, everything works perfectly, equal roads and clean logs for everyone

[manyrin2022]

https://datazap.me/u/manyrin2022/log...47-48-49-50-51

Logging at the moment when problems with the crankshaft sensor began

[manyrin2022]

Update 06.01.2026

[BashShah]

Ok historically speaking.
If 1 Thing goes with the DME and you dont know what caused the issue in the First Place.
So Chances that the Culprit is still causing the issue.
The Culprit is still at it.

Mt only 2 cents, is maybe your version of DME may or may not like the Tune.
Have you tired Stock to rule out if any of you Mods may be the issue?
If it is not your Mods.....then it may just verywell be a faulty DME.

I have had a DME issue which was caused by O2 Sensor wires shorting and making contact in extreme conditions on a N54. and I ended up replacing the DME and reprogramming the CAS Module.

[manyrin2022]

Originally Posted by BashShah

Ok historically speaking.
If 1 Thing goes with the DME and you dont know what caused the issue in the First Place.
So Chances that the Culprit is still causing the issue.
The Culprit is still at it.

Mt only 2 cents, is maybe your version of DME may or may not like the Tune.
Have you tired Stock to rule out if any of you Mods may be the issue?
If it is not your Mods.....then it may just verywell be a faulty DME.

I have had a DME issue which was caused by O2 Sensor wires shorting and making contact in extreme conditions on a N54. and I ended up replacing the DME and reprogramming the CAS Module.

I, along with other craftsmen, believe that the problem is precisely in the reflex, since it is a tuning part that is directly connected to the crankshaft sensor and has a connector into which the factory crankshaft sensor wire is connected. The first time the problem appeared, in my opinion, the problem was not correctly identified and accidentally repaired something that did not need to be repaired, since yesterday I, together with the craftsman, removed the reflex adapter that is responsible for receiving data from the crankshaft sensor and directly connected the factory wiring and everything works fine, then we returned this reflex connector and within the next 2 hours the problem did not return, if it appears again, I will completely redo the reflex wiring that is connected to the crankshaft sensor.

But what worries me more is that Motiv Reflex ignores my messages, including Visconti tuning, and I think they just don't want to help.

[manyrin2022]

Update 09.01.2026

[manyrin2022]

Datalogs:
There were no errors (before receiving errors), they appeared 2-5 minutes after writing this file. https://bootmod3.net/log?id=695d5defe08d5e45fd6fdc60

It is already recorded here when the errors appeared, so the recording shows that the car is in an emergency state to preserve its condition. https://bootmod3.net/log?id=695d5da2e08d5e45fd6fdc5a

But here, the crankshaft sensor was connected directly to the factory wiring, there were no errors during the 2 hour drive. https://bootmod3.net/log?id=69600b43e08d5e45fd700d94

[manyrin2022]

Update 29.01.2025

[manyrin2022]

Resolved