As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB, THE ALTIMETER AND BOTH THE NR 1 AND NR 2 ATC TRANSPONDERS FAILED AND THE AUTOPILOT WOULD NOT ENGAGE. THE AIRCRAFT RETURNED TO DTW AND LANDED WITHOUT INCIDENT. REPLACED THE AIR DATA COMPUTER AND THE NR 2 ATC TRANSPONDER, OPERATIONAL CHECK GOOD.