How To Fix GG656 - No unit field has been defined for the field group 'Quantity'

SAP Error Message - Details

• Message type: E = Error

• Message class: GG - Messages for FI-SL customizing

• Message number: 656

• Message text: No unit field has been defined for the field group 'Quantity'

What causes this issue?

You have defined period fields for quantities (MSLXX). However, you
must include a unit field for the quantity as a key in the definition
of the table. This key must be called 'RUNIT'.

System Response

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

How to fix this error?

Define the key field 'RUNIT'.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message GG656 - No unit field has been defined for the field group 'Quantity' ?

  The SAP error message GG656, which states "No unit field has been defined for the field group 'Quantity'," typically occurs in the context of SAP's configuration for field groups, particularly when dealing with quantity fields in various modules such as Materials Management (MM) or Sales and Distribution (SD).
  Cause:
  The error arises when the system expects a unit of measure (UoM) to be defined for a quantity field, but it is not configured correctly in the system. This can happen due to:
  
  Missing Configuration: The unit of measure for the field group related to quantity has not been defined in the system.
  Field Group Settings: The field group settings may not have been properly set up to include a unit of measure.
  Custom Development: If there are custom developments or enhancements, they may not have accounted for the unit of measure.
  
  Solution:
  To resolve the GG656 error, you can follow these steps:
  
  
  Check Field Group Configuration:
  
  Go to the configuration settings for the field group in question. This can typically be found in the IMG (Implementation Guide) under the relevant module (e.g., MM or SD).
  Ensure that the field group for 'Quantity' includes a unit of measure field.
  
  
  
  Define Unit of Measure:
  
  If the unit of measure is missing, you need to define it. This can be done in the relevant configuration area (e.g., defining units of measure in MM).
  Navigate to the transaction code OMN1 (for defining units of measure) and ensure that the necessary units are defined.
  
  
  
  Check Custom Code:
  
  If there are any custom developments or enhancements, review the code to ensure that it correctly handles the unit of measure for quantity fields.
  Make necessary adjustments to include the unit of measure in the relevant logic.
  
  
  
  Testing:
  
  After making the necessary changes, test the transaction or process that was causing the error to ensure that it has been resolved.
  
  
  
  Consult Documentation:
  
  If you are unsure about the configuration steps, refer to SAP documentation or consult with an SAP functional consultant who specializes in the relevant module.
  
  
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as OMN1, MM01 (Create Material), or VA01 (Create Sales Order) depending on where the error occurs.
  SAP Notes: Check SAP Notes for any known issues or patches related to this error message.
  User Forums: Consider visiting SAP community forums or user groups for additional insights and solutions from other users who may have encountered the same issue.
  
  By following these steps, you should be able to resolve the GG656 error and ensure that the unit of measure is properly defined for the quantity field group in your SAP system.