As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
JUST PRIOR TO PUSHBACK DETECTED SLIGHT ODOR AFTER ENGINE START. CYCLED PACKS AND GASPER FAN ODOR GOT PROGRESSIVELY WORSE, SEEMED CONFINED TO THE COCKPIT. ISOLATED SMELL TO COCKPIT CEILING. FOUND EMERGENCY EXIT SIGN RELAY BAD. REPLACED SAME, NO OTHER FAULTS FOUND. EMERGENCY EXIT SIGNS CHECK NORMAL.