As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT OUTBOARD WING DEICE BOOT INOP LIGHT IN ICING CONDITIONS. RETURNED TO SFO. RE-CHECKED INFLATION OF LEFT AND RIGHT OUTBOARD WING BOOTS. FOUND GOOD. SWAPPED LEFT AND RIGHT OUTBOARD WING BOOT PRESSURE SWITCHES FOR TROUBLESHOOTING. RAN ENGINES. OPERATIONAL CHECK OF DEICE SYSTEM GOOD.