As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SHORTLY AFTER ARRIVING AT THE GATE WITH APU RUNNING, SMOKE APPEARED IN COCKPIT & CABIN, FOLLOWED BY LT PACK AUTO FAIL CAUTION. PERFORMED FIM TASK 21-22-00-810-806 & FOUND SOURCE OF ODOR & SMOKE TO BE COMING FROM THE LT PACK, DEFERRED LT PACK. R & R LT ACM IAW AMM 21-51-08. OPERATIONS CHECKED GOOD. MEL RESTORED.