SAP ERP ECC Warranty Inheritence in Functional Locations / Equipments (customer warranty,time-based)

[DAcker]

Hello experts!

I would like to use the SAP Standard feature to inherit the Warranty date from a functional location (FLOC) to subordinate FLOCs and subordinate equipments. 

I read the SAP documentation and a lot of community posts. Nevertheless, it is still not working in our ERP ECC system - unfortunately....

We want to use the warranty time-based only and as customer warranty. (not counter-based, no supplier warranty). 

Therefore, I enter the warranty start and end date in the superior FLOC. Both checkboxes are ticked for "inherit warranty" and "pass on warranty". Nevertheless, I create a new subordinate FLOC and the warranty is not transfered. Installation or removal of the FLOC is not triggered the inheritence too... 

What is wrong? 
What prerequisites are necessary? 

Is it correct that the master warranty is only needed for counter-based warranty tracking?

Thanks in advance!

Best regards,
Deborah