Honda BF115A, BF130A Outboard Motors Shop Manual., Page 127Get this manual
HONDA BFI 15A-130A
From 5-40
1) Turn the ignition switch OFF2) Connect the test harness to the ECM and the connectorNote that the test harness sensor connector must be disconnected at this time3) Turn the ignition switch ON4) Measure the voltage between the test box's positive +I A15 terminal and the negative (-1 A33 terminal