What was found
FLIGHT DECK DOOR DID NOT OPEN AFTER CONDUCTING TEST DURING ORIGINATING CHECKLIST/FLOW. TEST BUTTON PUSHED, WORKED PROPERLY; EMER ENTRY PUSH BUTTON IN PASSENGER CABIN PUSHED, INHIB PUSHED AND RED LED ILLUMINATED; EMER ENTRY BUTTON PUSHED AGAIN, GREEN LED DID NOT ILLUMINATED, NOR DID THE DOOR UNLOCK AFTER THREE CYCLES. DOOR REMAINED LOCKED UNTIL THE LOCK BUTTON WAS PUSHED TO OPEN DOOR. ( FLIGHTDECK SECURITY DOOR AUTOMATIC LOCKING SYSTEM ). REMOVED FROM SERVICE. R+R COCKPIT DOOR LOCK REF E175 AMM TASK 52-51-03-000/400-801-A OPS CHECK GOOD. NO FURTHER DEFECTS. CB RESET PLACARDS REMOVED AND MTX CONTROL NOTIFIED. AIRCRAFT RETURNED TO SERVICE.