How to check possible causes if MRP does not create any proposals

Purpose

Explains the cause of no proposals and their respective solutions.

Overview

The MRP sometimes does not create any proposals, e.g. planned order, purchase requisition, schedule lines, even though there is shortage for requirements. The root causes are not so clear.

 Here are some cases can be checked one by one.

Case 1: The total planning of MRP cannot generate any proposals.

If you ran the total planning of MRP, e.g. MD01 or MDBT and no proposals were generated, please run MD03 for the material/plant, if this can create it means that the planning file entries of the materials are missing or the corresponding planning indicator, e.g. NETCH is missing in the planning file entry. Please go to the transaction MD21to check if the planning file entry exist, if there is not or no NETCH indicator is set then the system may not run the material in the total planning of MRP.
When the user run the total planning of MRP with the parameter NEUPL the system only runs the materials whose planning file entries exist (In this case, the NETCH indicator is not checked.). When the total planning of MRP is done with parameter NETCH, only the materials whose planning file entries exist with indicator NETCH are planned. But if you run MD03, the system does not check planning file entry since the system is told what material should be run.

Please create the planning file entry in MD20 or make some changes of MRP related object in order to set the flag. Running the transaction MDAB can automatically detect the missing planning file entries and create them but this does not set the NETCH indicators for the existing planning file entries.

Normally the planning file entry will be created automatically while the material is created or set the flag automatically when user make changes of MRP related.

The following note provides more details about the planning file entry:

SAP Note: 1890440 - Materials are not planned by MRP

Case 2: There is a requirement from safety stock in MD04 but this is not considered in MRP as the screen below.

If the material has a material group in the material master, please go to the customization transaction OPPR.

Input the plant and MRP group, then click the button 'Safety Stock', then the screen below is displayed.

If there is a value in the field 'Share SStk' as above, this means that the percentage of the safety stock can be used to cover the requirement.

 e.g. there is a requirement of safety stock 100, and the 'Share SStk' has the value 100 in the OPPR, then the quantity 100 * 100% = 100 will be used to cover its requirement. Since this can cover  the safety stock itself no proposals are needed. 

See note 1704074 for more details.

Case 3: No proposals are created for the requirement of PIR (Planned independent requirement).

The PIR exist as below in MD04, but proposales, e.g. planned orders, are not created after running MRP.
In this case, please check if the MRP group is maintained for the material, if yes, then go to the customization below to check if the PIRs lie in the period of Adjustment.
SPRO > Production > Production Planning > Demand Management > Planned Independnet Requirements > Maintain consumption mode and period of adjustment.
Double clikc the line for the plant and MRP goup, the screen below is displayed.

The 'Adjustment: Planned Ind. Reqmts' value 1 means that the period is calculated forward from today, and the field 'Adjustment Period: PIRs' is the period by working days.
E.g. Today is 29.09.2011, plus 7 working days forward it goes to 10.10.2011. Since the PIRs lie before this date they are not included in the MRP calculation and no proposals can be created for them.

See also note 1825187.

Case 4: The dependent requirements are not considered in MRP.

There is dependent requirements (Order Reservations in this case) with quantity 100 in the screen below, but no proposal is created.

After checking, it is turned out that the value 1 'Materials for dependent requirements are not planned' in the field 'MRP dep.requirements' of MRP 4 view of the masterial master as below.

 Resetting the the field can create the proposals by MRP.

See also note 1825187.

Case 5. Sales documents are not considered in MRP.

In the exmaple above, sales order 14144 is displayed but is not considered in MRP (No quantity is reflected in column 'Available Qty'.

 
It happens because the field 'No MRP' has value 1 'Requirement not planned, but displayed' in customization transaction OVZG as above for the requirement class of the sales document.
If that is blank, the sales document can be planned by MRP. If that has value 2, the sales document doesn't appear in transaction MD04.
To get the requirement class of sales document, check requirement type in field BEDAE of table VBAP, go to customization transaction OVZH as following to find the requirement class by requirement type.

 
Then, the class, e.g. 030 in this example, can be checked in transaction OVZG.
 

 In addition, the sales order is not considered in MRP if the schedule line category which doesn't allow MRP is set in the order even though field 'No MRP' is set to consider it in transaction OVZG for requirement class. In screen shot below, CP is the one allows MRP, CN doesn't.

Case 6. The MRP user exit M61X0001 implemented to exclude certain materials in MRP.

Please go to transaction SMOD or CMOD to check if the user exit is implemented.

Case 7. Some BADIs are implemented to exclude the MRP requirements.

The BADI MD_CHANGE_MRP_DATA contains many methods which can change or exclude the data read for net requirements calculation, e.g. the reservation, dependent requirements, planned independent requirements etc. Please go to transaction SE18, input the BADI MD_CHANGE_MRP_DATA into the field 'BADI Name', and click 'Dispaly', go to menu 'Implementation' > 'Overview' to check if there are your own implementations, if yes, double click that to check the source code of relevant methods.

The SCN document BAdIs for MRP provides more details about the BAdIs available on MRP.