As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTERÂ ENG START AND PUSH BACK , TURNED ON WING AND TAXI LIGHT AND STARTED LH PACK, COCKPIT FILLED WITH ACIDIC/ SMOKEY SMELL. TAXIED OUT BUT RETURNED TO GATE, SMELL DID NOT GO AWAY.(<P>PER CONVERSATION WITH CREW AND DVI OF LIGHT CONTROL PANELS, FOUND RUNWAY TURNOFF SWITCH BURNT AND ARCHING. R/R LIGHTING CONTROL PANEL ASSY PER AMM 33-13-00, OPS CHECK GOOD. NO FURTHER OVERHEATING/ ARCHING</P>)