As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING RON OUTBOUND FROM MSP, TCAS FAILED. WE RECEIVED ERRONEOUS TCAS TRAFFIC ADVISORIES (TA) AND RESOLUTION ADVISORIES(RA) AT VARIOUS ALTS. SWITCHED TO NR 1 AND WE STILL RECEIVED SOME ERRONEOUS WARNINGS (LESS FREQUENT) AIR RETURN TO MSP. MAINTENANCE REPLACED TCAS COMPUTER TESTED SYSTEM IAW FUNCTIONAL CHECK 34-44-00 P 5 01 ALL OPS NORMAL.