As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS NOT DECLARED DUE TO: LEFT DUCT PRESSURE WENT TO ZERO AFTER TAKEOFF, N1 SPLIT UP TO 4%, REPEAT WRITE UP. AIRCRAFT AIR INTERRUPTED BACK TO AND LANDED SAFELY AT DFW. REMOVED AND REPLACED MW0311 HARNESS ON LEFT ENGINE. OPERTIONAL CHECKS GOOD. PER AMM 73-21-06 AND REF NON-ROUTINE 3799342.