As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ETOPS SIGNIFICANT SYSTEM - L PIMU MSG ON ECS/MSG. TROUBLESHOOT WITH FIM 71-00-00. BITE OF PIMU SHOWED EEC CH A/B XTRN DISAGREE. EPCS PAGE 2 DOESN'T SHOW ANY LABEL BIT INFO FOR OVERSPEED CIRCUITS. ERASED L PIMU PERFORMED BITE AND RAN ENGINE MSG DID NOT RETURN.