Deactivate Account Assignment Elements in Controlling

Dear Experts

I request your kind support on the below issue.

We have deactivated 'Account Assignment Elements in CO' ( i.e, Fund and Budget period). Due to this when we post depreciation Fund is not geting updated to Expese GL line item (depreciation GL A/c).

Is this issue occurs because of deactivation Account assignment elements in CO or some thing elese.

And also kindly suggest the major impacts If we deactivate 'Account Assignment Elements in CO'. I red some help information but not able to understand the function completely. In our business there is no process of planning and report CO line items.

Also I woulk like to know when we deactivate account assignment elements in CO.

Kindly suggest,

Thanks in advance

Rao