I think Kia has been using them also. Perhaps due to they are more powerful? I ask as your into this stuff big time.
I have not seen K relay for KIA. The only other car than Volvo (p/n 1235893) that I know of which uses this type of relay is '98 Mercedes ML320 (maybe other models as well). I don't have the p/n but they call it K15 and it is yellow. Otherwise, the Bosch numbers are: 0 332 015 001 0 332 015 006 0 332 015 012 0 332 015 013
The K relay will not blow the fuse #10 because it is "before" the fuse. From the fuse #10, there are two branches: one to the tail lights (to the 2 inner of the 3 small bulbs) and to the license plate lights (from the RH tail light); the other branch goes to the instrument panel illumination etc. Partial short in one of these two branches is blowing the fuse. Before you start digging into the instrument panel, I suggested to do the much easier step first (in the other thread). The inline connector for the license plate lights is just below the RH tail lamp, easy the access.