As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RIGHT PACK LIGHT ILLUMINATED DURING TAXI, QRH ACCOMPLISHED LIGHT OUT UNTIL RECALL. ACFT GROUNDED. REPLACED THE RT PACK TRIM CONTROL VALVE. IAW AMM 21-51-10/401. OPS CHECKED GOOD. NO LEAKS NOTED. BITE CHECK OF RT PACK/ZONE CONTROLLER CHECKED GOOD.