Symptom
The pricing condition PR00 is marked as mandatory condition (T683S-KOBLI)in the pricing procedure (transaction V/08).
The same pricing procedure contains subsequent price conditions (conditions having Condition Class = B in V/06).
Due to the last price logic (see SAP note 836243) the PR00 price condition gets deactivated by one of the subsequent price conditions during SD document processing.
It means, KONV-KINAK / XKOMV-KINAK (condition inactive) is filled for PR00.
If you create a downpayment invoice, only the last active price condition is copied into the downpayment item and the deactivated PR00 condition is ignored. Since PR00 is a mandatory condition, the error message V1801 "Pricing error: Mandatory condition PR00 is missing" is displayed which hampers further activities.
Reason
It is the standard design of SAP system that inactive (KONV-KINAK) or statistical (KONV-KSTAT) conditions are not taken over into invoices having downpayment items.
For example billing type FAZ has downpayment items.
The following source code is responsible for this behaviour:
FUNCTION PRICING_COPY
...
* By default, statistic and inactive conditions are not copied
* in downpayment positions. By setting U15_SUBRC to '1' the
* copying is suppressed.
if konv-kstat ne ' ' or konv-kinak ne ' '.
u15_subrc = 1.
endif.
endif.
...
Solution
By using FORM USEREXIT_PRICING_COPY (RV61AFZA) you can easily change this behaviour and fulfill your requirement. Changing the field U15_SUBRC in the user exit achieves that statistical or inactive conditions are copied into downpayment items.
An example for the source code development:
USEREXIT_PRICING_COPY (RV61AFZA)
...
if ( konv-kstat ne ' ' or konv-kinak ne ' ' ) and amount_rule ca '45'.
u15_subrc = 0.
endif.
...
...