As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT "BLEED TRIP OFF" LIGHT ILLUMINATED AT TOP OF DESCENT FL400. QRH CHECKLIST ACCOMPLISHED. LIGHT OUT AND PACK RESET WITH TRIP RESET PUSHED. ACFT GROUNDED. PERFORMED FIM TASK: 36-10, TASK 801. STEP E(2) DROVE TO ACCOMPLISH "PRELIMINARY CHECKS" FAULT ISOLATION PROCEDURES-STEP F, 2, B. FOUND BINDING HIGH STAGE VALVE ON THE NR 1 ENGINE REPLACED HIGH STAGE VALVE & INSTALLED NEW. REF: AMM 36-00-00. ACFT OK FOR SERVICE.