As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
TAXIING OUT, ON RECALL LT PACK LIGHT ILLUMINATES, GOES OUT WITH RECALL. WITH MEL 21-5D ALREADY APPLIED, MAINTENANCE CONTROL HAD US RETURN TO GATE. ACFT GROUNDED. ACCOMPLISHED BITE TEST OF LT PACK/ZONE TEMP CONTROLLER IAW AMM 21-61-00-700-806-002. ALL OPS TESTS AND VERIFY CHECK NORMAL. NO DEFECTS NOTED.