As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
TYS During a scheduled inspection, When doing inspection task card # 35-20-00-720-001-A00, the cabin oxygen masks did not deploy in auto mode. Maintenance removed and replaced the altitude sensing switch. I.A.W.-EMB-135-AMM-51-40-02. operational checked good. Repair procedures where satisfactory, aircraft will be released upon complection of inspection.