Issues after DCT GTS tune

[maicol76]

After updating DCT stock software to GTS ver. about two years ago, I’ve occasionally experienced an issue where the transmission is not recognized.

Normally, when I unlock the doors, the gear selector light turns on and the gear position is displayed on the cluster.
However, sometimes these don't appear even after unlocking the door, and in this situation, even when I insert the key and turn on, nothing changes. No gear position is shown on the cluster, and the gear selector light stays off, and engine cannot be started.

If I turn ignition button OFF and ON once or several times, it starts to work again, and after that, the transmission operates perfectly during track driving.
The issue disappears for a while and then reappears occasionally.

While searching through this forum, I came across a thread mentioning that oil intrusion in the area where TCU is located could cause such an issue.
but assuming that’s not the case, what else could be the cause?
I’m not sure where or how to start troubleshooting, so I would appreciate any advice.

The wake-up signal voltage at the gear selector is always measured as normal under all conditions.

% ChatGPT mentioned that this issue sometimes happens with the GTS version of the software. I’m not sure if that’s true.

[maddmatth]

Try get the software reflashed and make sure it's the latest version? But yeah that does sound more likely to be a hardware/electrical issue.

[omgzirra_exe]

its always a ground issue.

[maicol76]

Originally Posted by omgzirra_exe

its always a ground issue.

People always jump to conclusions so easily.
It’s been over ten years since I installed two ground wires thicker than stock, one for engine and one for transmission except for exhaust ground.

[maicol76]

Originally Posted by maddmatth

Try get the software reflashed and make sure it's the latest version? But yeah that does sound more likely to be a hardware/electrical issue.

Thank you for your reply.
I recently reinstalled the SP-Daten V70 version, but the symptom remains the same. I'm also considering the possibility of a hardware issue, but trying to first identify whether it might be a software related problem.

[omgzirra_exe]

Originally Posted by maicol76

People always jump to conclusions so easily.
It’s been over ten years since I installed two ground wires thicker than stock, one for engine and one for transmission except for exhaust ground.

and guess what, every DCT error that is not a mechatronics failure is a ground issue, worse case hardware issue with GWS, but that would all appear obvious.

a ZB change to GTS for your trans isn't going to cause any failures, all it does is change torque % and clutch line pressure.

[maicol76]

00CDB4
00CDB8
00CD9D
00CD9E
00CDB0
00D357
00E094
00E097

My M is a 2011 E92 M3 Euro ver., and the DCT HW NO. is 798. I updated it with GTS ver. 773.

When the symptoms occur, these codes appear. Then, when the symptoms disappear, the codes also clear themselves. In my limited understanding, I believe these codes are not the root cause but rather the result of some underlying issue.

The battery voltage is above 13V, and ground cable is ok.
I also came across a post suggesting that the issue might be due to the TCU booting late because of a delayed wake-up signal, meaning the TCU does eventually boot up, but the system fails to recognize it due to a timing gap.

Any advice or insight would be greatly appreciated.

% My M is a track-only vehicle, and I've been running it for several years with almost all components removed, without any issues.
However, after updating to the GTS software and doing a few track sessions, the problem suddenly started to appear.

For reference, during the GTS tuning process, the upload occasionally gets interrupted, but when I resume it, When I resume it, it’s recognized normally and the update completes successfully.

[maicol76]

Originally Posted by omgzirra_exe

and guess what, every DCT error that is not a mechatronics failure is a ground issue, worse case hardware issue with GWS, but that would all appear obvious.

a ZB change to GTS for your trans isn't going to cause any failures, all it does is change torque % and clutch line pressure.

Thank you for your advice.
However, I have already checked the grounding twice, the stock one, the two I’ve maintained for a long time, and I’ve even tried replacing the cables. Yet, the situation remains the same.
If there are any other parts where I should check the grounding, I would really appreciate it if you could let me know.

I'm also aware of how software updates affect the operation of the mechatronics. I have tested the GTS, CRT & EURO ver., but the situation remains unchanged. At this point, I would almost prefer it to be a hardware issue. I just hope it’s not oil intrusion in the TCU, because that would require removing the transmission from the car.