As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) ON TAKE, THRUST REVERSER ISOLATION VALVE WARNING LIGHT ILLUMINATED. RETURNED TO YYZ. THRUST REVERSERS OPERATED AS PER WORK CARD 1187, COULD NOT DUPLICATE DISCREPANCY. REPLACED NR 1 AND 2 THRUST REVERSER PRESSURE SWITCHES PER MM 78-31-16. OVERWEIGHT LANDING CHECK COMPLETED AS PER FLYAWAY MANUAL PAGE 02.01.01, NO FAULTS NOTED.