As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON TOUCHDOWN MAINT ON OVERHEAD PANEL ILLUMINATED. GROUNDED - YES. LAST LEG STATUS MESSAGE 21-6515 "CONTROL CABIN TRIM AIR VALVE SIGNAL OUT OF RANGE". PERF B737-9 IFIM 21-61-00-810-841. BITE TEST OF R/H IASC - TEST PASS - FAULT RESET / MAINT LIGHT EXTINGUISHED. ETOPS GND VERIFICATION TEST PASS.