As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLAPS FAIL CAUTION ON APPROACH. ONLY 20 DEGREES FLAPS WAS OBTAINED. WENT AROUND AND DID QRH. LANDED WITH FLAPS AT 20 DEGREES. RIGGED FLAPS PER MM 27-51-00. REMOVED AND REPLACED LEFT BPSU IAW CRJ MM 27-51-10. CYCLED MULTIPLE TIMES, NO FURTHER FAILURES. OPS CHECK GOOD.