What is the purpose of measuring AC voltage output at the stator with the engine running?

Measuring the AC voltage output at the stator with the engine running serves to assess the functionality of the charging system. In four-stroke engines, the stator generates AC voltage which is then converted to DC voltage for charging the battery and powering electrical components. If the AC voltage output is within the specified range while the engine is running, it indicates that the stator is functioning properly and that the charging system is capable of delivering the necessary power.

Low or no AC voltage output may point to issues such as a malfunctioning stator, wiring problems, or other faults within the charging system, which can lead to battery depletion and affect overall engine performance. Regular checks of the AC output are important for maintaining reliable operation and ensuring that the electrical system is performing as expected.