Troubleshooting - Doosan G643E Service Manual

Troubleshooting

Charging system defect is almost caused by lack of
pan belt tension and faulty function of wiring,
connector, and voltage regulator.
One of most important thing during troubleshooting
of charging system is determining the reason
between overcharging and lack of charging. So,
prior to inspection of alternator, check the battery for
charging. Faulty alternator causes the following
symptoms.
1. Faulty battery charging
1) IC regulator fault (Short circuit)
2) Field coil fault
3) Main diode fault
4) Stator coil fault
5) Brush contact fault
2. Overcharging : IC regulator fault(Short circuit)
Other faults such as voltage adjusting problem
except above symptoms rarely happen.
G643(E) Service Manual 127 Chapter 4. Engine Electrical System