How do you test trigger coil on Yamaha atv100?

To test the trigger coil on a Yamaha ATV 100, first ensure the ignition is off and disconnect the wiring harness from the coil. Use a multimeter set to the ohms setting to measure the resistance across the coil's terminals; refer to the service manual for the specific resistance range for your model. If the reading is outside the specified range, the coil may be faulty and should be replaced. Additionally, you can check for continuity to ensure there are no breaks in the coil wire.