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Diagnostic Procedures

  1. Verify battery cable connections are clean and tight. Check battery hydrometer eye. If eye is Yellow or clear, replace battery. If eye is not Yellow or clear, go to next step.
  2. If battery hydrometer eye is Green, go to next step. If hydrometer eye is not Green, charge battery.
  3. Perform battery load test. If battery passes load test, go to next step. If battery does not pass load test, replace battery.
  4. Perform charging test. If vehicle passes charging test, check for parasitic load or driving habits. If vehicle does not pass charging test, go to next step.
  5. Check for DTCs. If DTC P0562 or P0621 is stored, diagnose affected DTC(s). If DTC P0562 or P0621 is not stored, go to next step.
  6. Replace generator. Verify charging system operation.
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