How To Fix MM656 - Unit of measure &1 cannot be used because is is not maintained

SAP Error Message - Details

• Message type: E = Error

• Message class: MM - Messages for material master maintenance and Customizing

• Message number: 656

• Message text: Unit of measure &1 cannot be used because is is not maintained

What causes this issue?

You tried to enter unit of measure &v1&, which has not yet been
maintained as a base unit of measure or alternative unit of measure for
the material. You are not authorized to maintain central material master
data (authorization object M_MATE_MAN). This means that you are not
authorized to create new alternative units of measure, either.

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

System Response

It is not possible to use unit of measure &v1&.

How to fix this error?

Use a unit of measure that already exists, or contact your system
administrator to ask for the authorization to maintain central material
master data.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message MM656 - Unit of measure &1 cannot be used because is is not maintained ?

  The SAP error message MM656 indicates that a specific unit of measure (UoM) cannot be used because it is not maintained in the system. This error typically occurs in the Materials Management (MM) module when trying to perform operations involving materials that require a specific unit of measure that has not been defined or activated in the system.
  Cause:
  
  Unit of Measure Not Defined: The unit of measure you are trying to use is not defined in the system.
  Unit of Measure Not Maintained for Material: The unit of measure is defined but not maintained for the specific material in question.
  Incorrect Configuration: There may be issues with the configuration of the unit of measure in the system settings.
  
  Solution:
  To resolve the MM656 error, you can follow these steps:
  
  
  Check Unit of Measure Definition:
  
  Go to transaction code CUNI (Unit of Measure Conversion).
  Check if the unit of measure (UoM) in question is defined in the system.
  
  
  
  Maintain Unit of Measure for Material:
  
  Go to transaction code MM02 (Change Material).
  Enter the material number and select the appropriate views (e.g., Basic Data 1, Purchasing, or Sales).
  Ensure that the unit of measure is maintained in the relevant views. If it is missing, add it.
  
  
  
  Check Material Master Data:
  
  Ensure that the material master data is complete and correctly configured.
  Verify that the UoM is assigned correctly in the material master record.
  
  
  
  Check UoM Group:
  
  Ensure that the unit of measure is part of the correct UoM group.
  You can check this in the material master under the Basic Data view.
  
  
  
  Configuration Settings:
  
  If you have access, check the configuration settings for units of measure in the IMG (Implementation Guide).
  Navigate to Logistics - General > Material Master > Basic Settings > Units of Measure to ensure that the UoM is properly configured.
  
  
  
  Consult Documentation:
  
  If you are unsure about the steps or need further assistance, consult SAP documentation or reach out to your SAP support team.
  
  
  
  Related Information:
  
  Unit of Measure Types: Understand the different types of units of measure (e.g., base unit, alternative unit) and how they relate to each other.
  Material Master Views: Familiarize yourself with the various views in the material master that may affect the unit of measure.
  SAP Notes: Check for any relevant SAP Notes that may address specific issues related to unit of measure maintenance.
  
  By following these steps, you should be able to resolve the MM656 error and ensure that the unit of measure is properly maintained in your SAP system.