Diagnosis The charging system requires little maintenance. The battery should
and Testing be fully charged and connections kept clean and tight.
Diagnosis of charging system problems is typically straightforward. Problems may be electrical or mechanical.
The troubleshooting flow diagram on the next page lists the most common charging system problems, the possible cause, and
recommended actions to resolve the problem.
Begin with a thorough visual inspection. If this fails to turn up the
possible cause, several tests are available to help you find the problem:
• Alternator output test (no load)
• Alternator output test (with load)
• Voltage drop tests
• Charging current relay test
• Diode tests