2007-2009 Yamaha F15/F20 Outboard Service Manual, Page 243Get this manual
Electrical system NOTE: Before measuring the peak voltage, check all wiring for proper connection and corrosion, and check that the battery is fully charged Use the peak volt adapter with the recommended digital circuit tester Connect the positive pin of the peak volt adapter to the positive terminal of the digital tester, and the negative pin to the negative terminal When measuring the peak voltage, set the selector on the digital circuit tester to the DC voltage modeDigital multimeter: YU-34899-A Peak volt adapter: YU-39991
Checking the electrical component
Measuring the peak voltage
To check the electrical components or measure the peak voltage, use the special service toolsA faulty electrical component can be easily checked by measuring the peak voltageThe specified engine speed when measuring the peak voltage is affected by many factors, such as fouled spark plugs or weak batteryIf one of these factors is present, the peak voltage cannot be measured properly