Diode Test

Connect DC clip-on probe from engine tester with oscilloscope to positive battery terminal. See Fig 1 . Start engine. Switch on low beam. Access diode test at 3000 RPM. See Fig 2 -Fig 4 . Replace generator as necessary.

Fig 1: Identifying Oscilloscope Connection

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Fig 2: Identifying Oscilloscope Patterns (No Fault Indicated)

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Fig 3: Identifying Oscilloscope Patterns (Positive Diode Defective)

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Fig 4: Identifying Oscilloscope Patterns (Negative Diode Defective)

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