As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FOUND CB B4 ON P6-2 POPPED. GROUNDED - YES. CB AFCS SYS B "ENGAGE INTLK" POPPED. PERFORMED INSPECTION PER B737-9 AMM 20-61-01. CB STAYS IN AND NO DEFECTS NOTED. PERFORMED DFCS BITE AUTOTEST PER AMM AMM 22-11-00-740-814 STEP B1F SYS A+B. NO FAULTS.