Manual Pricing Condition Add parameters

Hii Experts,

                              I want to add Z pricing condition into the service order item and the pricing condition is manual pricing condition I used the following FM but it is not adding the pricing condition .

                                   CALL FUNCTION 'CRM_ORDER_MAINTAIN'

                                        EXPORTING

                                                  it_pridoc                = lt_pridoc

                                        CHANGING

                                                  ct_orderadm_i        = crm_it_item

                                                  ct_input_fields        = it_input_fields.

Please provide your valuable suggestions.

Regards,

Shahezad