As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON TAXI IN LT OIL FILTER BYPASS LIGHT ILLUMINATED FOR NR 1 ENGINE. ENGINE WAS SHUT DOWN IAW QRH. ACFT GROUNDED. ACCOMPLISHED FIM 79-05, TASK 817 & 79-21 TASK 806. FOUND FAULT CODE 79-31121, DUAL CHANNEL SIGNAL DISAGREE. REPLACED NR 1 ENG SCAVENGE OIL FILTER CLOGGING TRANSMITTER REF MM 79-21-07-400-801, STEPS 3 F.(1) - 3.H.(3). ACCOMPLISHED CLOGGING TRANSMITTER INSTALLATION TEST REF MM TASK 79-21-07-400-801, STEP 1.