As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RIGHT "PACK" LIGHT ILLUMINATED AT THE GATE. BOTH PACKS IN AUTO. ATTEMPTED "TRIP RESET". "PACK" LIGHT ILLUMINATED AGAIN. GROUNDED - YES. BITE OF #2 CONTROLLER SHOWS TCV FAULT ON VERIFY. PACK LIGHT COMES ON AFTER DEMAND IS PUT ON RIGHT PACK. REMOVED AND REPLACED R/H PACK TCV IAW B737-900 AMM 21-51-10. OP CHECKS NORMAL. BITE CHECK SHOWS NO FAULTS.