[boyt911sc]

Ulrich,

First of all, check if the horn relay and the relay socket match or compatible for your need. Do this investigation:
Test 1: Determine the terminals in the socket that are bridged or jumpered. There should be only two (2) bridged terminals. If yes, continue.....

Test 2: Check if these two (2) bridged terminals coincide with pin #30 and #86 (relay socket). If, yes, continue.......

Test 3: Plug the horn relay to the socket. There will be four (4) terminals/wires that will be bridged at this point. The single terminal that is not connected to these four is terminal #87.

Test 4: Check if this isolated terminal coincide with pin#87 (relay). If yes, then the rest of the terminals could be easily identified accordingly. Keep us posted.

Tony