As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EMERGENCY LIGHTS FLICKERED WHEN PROP HEAT SELECTOR ON EITHER TIMER. INSPECTED NR 1 AND 2 BRUSH BLOCKS, WIRING AND SLIP RINGS. CLEANED BOTH SLIP RINGS. NO FAULTS NOTED. REMOVED AND REPLACED THE NR 1 BRUSH BLOCK IAW MM 61-10-11. OPS CHECKED GOOD. OKAY FOR SERVICE.