>---------
>update vehicle set brc_id=(select co_brc from co_temp where cbpo_ref = cbpo_num) where empty(brc_id)=.t.
>---------

Is cbpo_ref a defined varaible with the correct type? Have you tried it like this:

update vehicle set brc_id=(select co_brc from co_temp where cbpo_ref = ?cbpo_num) where empty(brc_id)

BOb