As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) AT 100 HR INSPECTION, TEST OF ACTUATOR SWITCHES-ONE SWITCH FAILED THE TEST. INSPECTION OF THE SWITCH REVEALED THAT THE ACTUATOR BUTTON ON THE SWITCH WAS WORN TO ABOUT 1/2 OF IT'S ORIGINAL HEIGHT. INSTALLED A NEW SWITCH. SUSPECT FAN IMBALANCE TO BE THE CAUSE OF THIS WEAR.