On the standard MRP procedure, when material variants are used, the configuration should be copied directly and only from the material master classification. Note 416174 provides the following explanation of the system standard design:
"System design: When you create order proposals using the material requirements planning, always the more specific characteristic valuation of the requirements is preferred over the general characteristic valuation of the material. This is valid both for planning configurable material as well as for planning configured materials.
For configured materials (material variants, storage types) the material requirements planning assumes that all existing requirements do not have any characteristic valuation or are valuated according to the configuration of the material. This is at least ensured in the BOM explosion of the material requirements planning, where the configuration of the order header is only inherited by the configurable components, not by the configured components.
In addition to dependent requirements there can also be planned independent requirements for configured materials that have a configuration not corresponding to the material master. Therefore, the configuration of the sales order item of a configured material can be changed at any time in the sales order. The changed configuration of the sales order is also transferred for configured materials to the corresponding order proposals.
The usage of the characteristic valuation of the requirements when planning a configured material is relatively unproblematic if the master data (BOMS, routings) of the configured material is not configurable itself.
If, however, the master data of the assigned configurable material is used in the planning, the material variant behaves exactly like a configurable material in the planning, that is, the master data is exploded according to the configuration of the requirements.
In scenarios where the configured material is basically planned with a planning strategy, that provides for a sales order planing or individual project planning, the usage of the configuration of the requirements does not result in planning errors.
The usage of the requirements configuration, however, becomes problematic in scenarios where planning strategies are used for a make-to-stock production. Due to the requirements grouping on a daily basis, requirements with different characteristic valuations can be combined to an order proposal. The order proposal receives the characteristic valuation of the first valuated requirement. Furthermore a differentiation of the various configurations in the inventory management (plant stock or storage location stock) is not possible."
Due to a program error, the configuration of the requirement was copied instead of the material master configuration. This program error was corrected on the standard system by note 1712759, which is included on the latest support packages. Now, the configuration is correctly copied from the material master, as explained above.
However, many SAP customers were used with the old system behavior, without the correction. This bug was used like a feature and the configuration was always copied from the requirement. In those cases, when there is no configuration on the material master, after the implementation of the correction, the BOM explosion may be affected, leading to the exception message "53: No BOM explosion due to missing configuration" for the planned orders.
Therefore, the following modification note was created, to bring back the old system behavior, where the configuration is copied from the requirement, even for a material variant:
1972831 - Exception message 53 in MD05: No bill of material explosion due to missing configuration
Please observe that this is a modification note, which must be re-implemented after each upgrade or support package.
See also "Strategies for Variants - Demand Management (PP-MP-DEM) - SAP Library" for more details about material variants.
