Hello mansy;

You could start by resetting the IOP to factory settings, and then re-commissioning it as described in this manual:

https://support.industry.siemens.com/cs/ww/en/view/57199302/35857939723

Hope this helps,

Daniel Chartier

Hello which leds is showing the G120 ?

Have you tried with another PM ?

Mansy305405

Hello all i have problem in SINAMICS G120 PM 240-2 & Control unit:CU240E-2 PN we trying to commissioning using IOP but the IOP output Message "" No Communication with drive " also the control unit can't see the power module or established Communication between each , by the way i measured the Input voltage to power module it was correct 390VAC no problem in supply to power module do any one have any idea about this problem 

 I had the same problem once time. The PM was new....i replaced it for a new one and work right. PM was bad, for warranty.