Yamaha EF4500iSE Theory & Diagnostics Manual page 59

GENERATOR SYSTEM
TROUBLESHOOTING CHART
WEAK OR NO AC CURRENT: SINGLE AC COIL MODELS
Start the engine.
Check the overload warning light.
DOES NOT LIGHT ON
Start the engine.
Check the pilot light.
DOES NOT LIGHT ON
No load engine speed inspection.
9 Operate the engine with no load.
2,600 r/min
GOOD
Main coil AC voltage inspection
9 Start the engine.
9 Connect the pocket tester to the White leads.
9 Measure the voltage. (Tester range: AC 300 V)
W
W W
Main coil AC voltage:
Refer to Service Data Section for Specifications 175 ~ 225 V at 20 °C (68 °F)
GOOD
*
WEAK OR NO AC CURRENT
LIGHT ON
LIGHT ON
OUT OF SPECIFICATION
Y
Y Y
TOO LOW
DOES NOT GENERATE
GENERATOR SYSTEM
Check the overload warning light.
LIGHT ON
Check the pilot light.
Check the throttle control system.
Refer to "THROTTLE CONTROL SYSTEM" in
CHAPTER 6.
Magnetic force is weak.
Replace the magneto rotor.
Main coil resistance measurement
9 Stop the engine.
9 Measure the resistance between the White leads.
(Tester range: Ω × 1)
Main coil resistance:
1.22 Ω ± 20% at 20 °C (68 °F)
Refer to Service Data Section for Specifications
SPECIFICATION
Replace the stator assembly.
2-25
5-8
Inverter Generator Diagnostics ELEC
DOES NOT LIGHT ON
W
W W
OUT OF SPECIFICATION