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Diode Test

Connect engine tester with oscilloscope. See Fig 1. Start engine. Switch on low beam. Access diode test at 3000 RPM. See Fig 2-Fig 5 . Replace generator as necessary.

Fig 1: Identifying Engine Tester With Oscilloscope Connection
G00316724Courtesy of MERCEDES-BENZ OF NORTH AMERICA
Fig 2: Identifying Oscilloscope Patterns (No Fault Indicated)
G00316725Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Fig 3: Identifying Oscilloscope Patterns (Pre-Fuse Defective)
G00316726Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Fig 4: Identifying Oscilloscope Patterns (Positive Diode Defective)
G00316727Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Fig 5: Identifying Oscilloscope Patterns (Negative Diode Defective)
G00316728Courtesy of MERCEDES-BENZ OF NORTH AMERICA.