Airbag failure on Punto MY 2004

[truckerkoenig]

Hi folks!
I have an issue clearing Aisbag faltcodes on my son's Punto. SRS (TRW brand) control unit can be adressed (and failures read out) with simple CN KLL to USB device, but I can not clear fault codes. Is thre any cheap trick needed? I pressed deleate fault button, but active failures and number of counts keeps same - also after ign off/on cycle.
Thanks for your support!
BR
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