As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
YYZ - CREW REPORTED THAT DURING CLIMB RIGHT ENGINE HAD A SURGE THAT WAS CONFIRMED WITH ENGINE GAUGES. EMERGENCY DECLARED RETURNED YYZ LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED T12 SENSOR THAT WAS FAULTED. SYSTEM GROUND CHECKED NORMAL OPERATION.