No-Load Check

NOTE: Use fully charged battery.

Connect voltmeter and ammeter. See Fig 1.
Run engine at idle up to 2000 RPM. Read meters. Amperage should be 10 amps (maximum). Voltage should be 14.4-15.0 volts (68°F (20°C).
NOTE: Consideration should be taken that voltage will differ somewhat with regular case temperature. See Fig 2.
If voltage is higher than standard value, check ground of brushes. If the brushes are not grounded, replace IC regulator. If voltage is below or in standard value, See step 4.
Ground "F" terminal and start engine. Measure voltage at "B" terminal . See Fig 3.
If voltage is higher than standard value, it is considered that generator itself is good but IC regulator has been damaged, replace IC regulator. If voltage is lower than standard value, generator itself has problem, check the generator.

Fig 1: Testing Generator Output (Typical)

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Fig 2: Identifying Undercharged Inspection Chart

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Fig 3: Grounding Generator "F" Terminal

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