Solved: (SZL-related) M-button/MDM not functional

[Bartledoo]

The previous owner replaced a faulty szl with the wrong part. Case closed.

[pyhee]

Originally Posted by Bartledoo

The previous owner replaced a faulty szl with the wrong part. Case closed.

Yes this is also probable. Let me dig into this the next time I go back to the dealer

[treishu]

Originally Posted by pyhee

Finally this project came to an end, the M button is back again! Here’s the summary.

Replacing part: SZL 61319123060
Actions required: LWS recalibration by Tools32

I ordered the SZL from another M3 produced in 2008. Swapped with the one I had (part # 61319123049). The car showed error code 005E50 for my DSC variant dsc_87, implying “DSC: Steering-angle sensor: serial number; calibration required”.

I used Tools32 to do the calibration by opening dsc_87.prg, running job Lenkwinkel_dsc_ausgleichen. Job done in 1 sec. (The method of turning the steering wheel full left, full right and then center did not work for M3.)

Now there's not any fault code about M-button or DSC. Everything works just fine. I am very satisfied.

The myth still exists; why my car, equipped with M-Drive, had a SZL which is not compatible with it? Is it due to a update in the DSC firmware so 123049 is no longer compatible?

Anyway thank you guys very much for the contribution. Your input helped a lot!

thank you for this topic
helped out alot

i was in the same situation but my car had multiple
previous owners and for sure someone replaced the szl

now it is finally working.

thank you very much

[pyhee]

Originally Posted by treishu

thank you for this topic
helped out alot

i was in the same situation but my car had multiple
previous owners and for sure someone replaced the szl

now it is finally working.

thank you very much

Hi treishu you are very welcome!

I helped my two other friends retrofitted MDM to their E9x M3s. The workflow was all the same. Nothing new to this thread