As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WITH NR 1 PNEUMATIC SYSTEM DEFERRED UNDER 36-01-A NR 1 SYSTEM IS STILL PROVIDING AIR TO RUN A-PACK WITH ISOL VALVES CLOSED & PNEUMATIC NR 1 SELECTOR OFF. WHILE DESCENDING WITH ALL THROTTLES IDLE, THE NR 1 PNEUMATIC PRESSURE WAS 15 PSI. PUSHED NR 1THROTTLE UP & PSI WENT TO 45 PSI. FOUND BROKEN WIRE ON CONNECTOR. CHANGED BROKEN CONNECTOR IAW SMP CHAPTER 20 DC10AMM.