As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON TAXI OUT DUCT LOW PRESS LIGHT CAME ON WITH DROP IN DUCT PRESSURE ON GAGE. ISOLATED LEFT WING PRESS LESS THAN 15 PSI. REPLACED PRESSURE REGULATOR VALVE ON ENGINE NR 2 PER MM 36-1114. PERFORMED ENGINE RUN PER MM 71-00-00. OPS CHECK OK.