As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTS COMING OUT OF FL220 CREW EXPERIENCED NR 1 ENGINE VIBRATION OF 7.5 UNITS AND THE A3 BREAKER TRIPPED, WITH ENGINE AT IDLE THERE IS STRONG AIRFRAME VIBRATION AND 1.5 UNITS INDICATED ON THE ENGINE. REPLACED ENGINE. REPLACED ENGINE DUE TO CHAFFED WIRES FOUND GROUNDED TO THE IGN POWER SUPPLY. DUE TO HIGH VIBRATION REPORTS ALL MAG CHIP DETECTORS WERE CHK'D WITH NO ANOMALIES FOUND. SUSPECT ICING AS CAUSE FOR VIBRATION.