Diagnosis
The tool is completely unresponsive. No motor movement or electronic sounds. This points to a break in the circuit between the battery and the motor controller.
How to Fix It
Perform a systematic check. 1: Confirm the M18 battery is fully seated in the trimmer's base. 2: Check that the two-piece shaft is fully connected and locked (see arrow alignment). A disconnected shaft breaks the power path. 3: Inspect the trigger for visible damage or obstruction. 4. Try a different M18 battery. If all checks pass, proceed.
If That Didn't Work
The internal wiring harness or motor controller has likely failed. There are no user-resettable fuses or circuit breakers. This condition requires professional service.
Heads Up
Do not attempt to open the motor housing or rear handle. The electronics are potted and not user-serviceable. Tampering voids the warranty.