What was found
***WHILE AIRCRAFT WAS IN FOR BRIDGING*** MAINTENANCE FOUND FWD LAV O2 MASK FAIL TO OPEN DURING OPERATIONAL CHECK. PERFORMED TROUBLESHOOTING OF FWD LAVATORY O2 BOX NOT DEPLOYING DURING OPERATIONAL CHECK. MANUALLY OPENED THE BOX AND REMOVED BOX FROM THE CEILING OF THE LAVATORY. FOUND CONNECTOR THAT DEPLOYS THE SWITCH NOT CONNECTED. RECONNECTED SPLICES AND PERFORMED OPERATIONAL CHECK OF PASSENGER OXYGEN DEPLOY-OPERATIONAL CHECK GOOD IAW AMM 35-21-00.