Purpose
To make full use of the reconciliation ledger functions you need to process some preparatory IMG activities:
Process Flow
The reconciliation ledger is updated online for all CO postings (see the IMG for Cost Element Accounting under Reconciliation Ledger
Activate Reconciliation Ledger)In the basic data for maintaining controlling areas, you can only display this indicator. This is because a deactivation with subsequent activation could cause data inconsistencies.
Any CO data that you post during the deactivation phase is not transferred to the reconciliation ledger. This data is not included during a CO-FI reconciliation.
You can store a document type for the reconciliation ledger in the basic data of the controlling area. The document type determines which document number interval is used for the FI documents. If you did not store a document type in the controlling area, you need to make an entry during the
reconciliation posting under Extras -> Posting parameters.For expense accounts, to which reconciliation postings are to be assigned, you must select Posting without tax allowed in the master record of the account.
These adjustment accounts must be profit and loss accounts (see
Defining Adjustment Accounts).To be able to make reconciliation postings in the FI component, you must define the adjustment accounts for secondary cost elements (see
Account Determination).To configure the various CO applications, see the information in the appropriate Implementation Guide (IMG).
You can create cost elements in the menus for Cost and Revenue Element Accounting or Cost Center Accounting.

When making a primary posting in Financial Accounting, you specify an account assignment object, for example, a cost center. If the reconciliation ledger is active, you can activate the validation indicator to ensure that the account assignment object (such as a cost center) is not assigned to a company code that differs from the one specified in Financial Accounting.
Select the appropriate indicator in the control indicator for your controlling area.
To do so, you need to select Business area balance sheets for the company codes assigned to the controlling area during the system settings for Financial Accounting. See the IMG Financial Accounting Global Parameters
The R/3 System then sets the Business area field as an obligatory field in the cost center master data.
For follow-up postings to the reconciliation ledger, the SAP R/3 System reads both the totals files and the line item files. This adversely affects system performance if large data volumes are involved. You should therefore run your follow-up postings in the background.