1990 Johnson Evinrude "ES" Cross V 88 thru 115, 150 thru 175, P/N 507874, Page 283Get this manual
High Voltage
In some conditions, the key switch may be shorting (some leakage) to the other terminals in the key switch, but will not show up with test light or an ohmmeterThis condition may be found by using condenser tester (leakage test) where voltage of approximately 500 volts is applied to the key switch terminalsWith all leads disconnected and the key switch in the "OFF" position, connect the black lead of the tester to one of the "M" terminals of the key switch1Attach the red lead apply leakage test
of the tester to the "B" terminal and
2Repeat test by moving the red lead to each of the terminals and applying the leakage testThe meter will indicate if leakage is present3When applying test to other "M" terminal, turn key to the "ON" position