1988 Johnson Evinrude "CC" 9.9 thru 30 Service Manual, P/N 507660, Page 149Get this manual
Runnin Tests Using C.DVoltm eter and AdapterAll odels The C.Dadapter permits tests on the charge coil, sensor coil, and power pack while the engine is running The connectors are plugged into the adapter ONE PAIR AT TIME and the jacks permit tapping the voltmeter into that particular circuit When the adapter switches are in the ON position, the circuit is complete through the adapter In the OFF position, the signal goes from the input side to the meter jack only, eliminating any influence from the output side of the adapter The engine will not run with switches in OFF position