As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING DESCENT FROM FL250, AS POWER WAS REDUCED BELOW 30 PERCENT TORQUE. WHEN DESCENDING THROUGH 23000` CABIN STARTED TO CLIMB RAPIDLY. DE-ICE PRESSURE CAUTION LIGHT ILLUMINATED. NO LOUD NOISES OR SQUEALS. MX INVESTIGATION FOUND RELAY 2121-K6 AT FAULT. RELAY REPLACED, ACFT RETURNED TO SERVICE. (NOTE: PART IS CONSIDERED AN EXPENDABLE AND TIMES NOT TRACKED, TIMES PROVIDED ARE AIRFRAME TIMES)