Starting/Charging Systems (H4SO): Generator: Inspection: Diode

2005 Subaru Outback i, StandardSECTION Diode
CAUTION: Never use a mega tester (designed for reading high voltage) or any other similar instrument for this test; otherwise, the diodes may be damaged.
  1. Checking positive diode Check for continuity between the diode lead and positive side heat sink. The positive diode is in good condition if resistance is 1 Ξ© or less only in the direction from the diode lead to heat sink.
    Fig 1: Checking Continuity Between Diode Lead And Positive Side Heat Sink
    G03828381Courtesy of SUBARU OF AMERICA, INC.
  2. Checking negative diode

Check for continuity between the negative side heat sink and diode lead. The negative diode is in good condition if resistance is 1 Ξ© or less only in the direction from the heat sink to diode lead.

Fig 2: Checking Continuity Between Negative Side Heat Sink And Diode Lead
G03828382Courtesy of SUBARU OF AMERICA, INC.
RENDER: 1.0x

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

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