Yamaha Outboard Motors Factory Service Manual F6 and F8, Page 446Get this manual
ELECTRICAL COMPONENTS ANALYSIS NOTE:
When measuring the peak voltage, set the selector to the DC voltage modeMake sure the peak voltage adapter lead are properly installed in the digital testerMake sure the positive pin (the "+" mark facing up as shown) on the peak voltage adapter is installed into the positive terminal of the digital testerThe test harness is needed for the following tests
Measuring steps: (1)Connect the peak voltage adapter probes to the connectors(2)Start or crank the engine and observe the measurement