1980 Johnson 4HP Service Manual, Page 41Get this manual
SENSOR COL TESTS Short to ground testWith 4-wire connector still connected to adapter, turn adapter switches OFF Set meter switches to and 5Clip bIack meter lead to armature plate and red meter ead in pinhole See Figure 4-23Crank engine and observe meterMove red meter ead to pinhole Crank engine reading either test means sensor coil is shorted to groundRepair replace Figure 4-24Power Pack Output Test Cranking
RUNNING TESTS USING C.DVOL AND ADAPTER
The adapter permits tests the charge coil, sensor coil and power pack while the engine is running The rubber connectors plugged into the adapter ONE TIME and the pin holes permit tapping the meter into that particular circuit When the adapter switches in the ON position the circuit is complete through the adapter the OFF position the signal goes from the input side to the meter tap onlyeliminating influence the output side of the adapterThe engine will not run with switches in OFF position
Figure 4-23Sensor Coil Short Ground Test
Output testWith red meter lead in pin hole place bIack meter lead in pin hole Crank engine and observe meterReverse leads and crank enginemeter reading of .3 volt means sensor cois If meter reads less than .3 volt replace sensor coil POWER OUTPUT TEST