1990 Johnson Evinrude "ES" Electric Trollers Service Manual, P/N 507869, Page 35Get this manual
OnOff SwitchFoot Control Models To avoid damaging components or troubleshooting equipment, disconnect the battery cables before proceeding1Loosen the bracket mounting screw(s) to access the switch terminals 2Use continuity light or ohmmeter calibrated on high ohms scale to test continuity
3When the onoff switch is "OFF": Meter must show no continuity between the two RED leads4When the onoff switch is "ON": Meter must show continuity between the two RED leads Meter must show no continuity between any lead and the switch's case Replace switch if your test results vary