1998-2006 Yamaha F20/F25 Outboards Service Manual, Page 409Get this manual
IELEe II=-:.i I CHARGING SYSTEM
CHARGING SYSTEM PEAK VOLTAGE
1Measure: Rectifierregulator output peak voltage Excessively over specification ReplaceExcessively below specification Check the lighting coilRectifierregulator output (RB) rmin Cranking
tCircuit: Loaded
2Measure: Lighting coil output peak voltage Below specification ReplaceLighting coil output peak voltage (YY) rmin Cranking