As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CABIN PRESS LIGHTS FLASHING ON ALL FOUR DOORS ON BLOCK IN,THE FLASHING STOPPED ABOUT 10 MINS AFTER BLOCK IN THIS WAS ALSO A PROBLEM BEFORE GETTING ON THE AIRPLANE EARLIER BUT THOUGHT IT WAS GROUND UNIT OVERPRESSURE IN YYC. REMOVED AND REPLACED FIN 14WN PRESSUER SWITCH - OPS CHK NML - MEL / PLAC RMVD.