You will need
  • tester (multimeter);
  • - screwdriver;
  • - pliers;
  • - serviceable intercom handset.
Talk to the neighbors and try to imagine the scale of the damage: the intercom is not working, on the floor or around the entrance. If problems with the intercom only occur in your apartment, unplug the cord from the handset of the intercom, then connect it back, reversing the polarity ("polarity").
Use a multimeter to check for voltage at the incoming power cord.
Check the address jumper to account for the shift, a little stir them and wipe with alcohol. If this does not help, one thing remains – to go to the store for a new tube.
Connect the proper tube short wire to the line directly in the dashboard. If the tube to work, look for broken wire or short circuit in the area from flap to your apartment.
Check for correct polarity connection on the switch. To do this, a multimeter, measure the resistance between bus "tens" and bus "units" in the presence of improper connections. The reason can be self-improper connection of the tube between the tire "units" or "tens" circuit one end of the tire "tens" or "units" on a metal body panel or the "break" one of the keys of the switch. In the first two cases it is necessary to restore normalcy to the transaction. In the latter case, it is necessary to replace the switch defective.
Contact the firm that installed the intercom system to provide you with the code administrator access. In case of refusal, please call the representative office of the manufacturer, putting them nine-digit number of your panel. View, not blocked your apartment programmatically set correctly numbering of flats in the stairwell, etc.
Call of the master, if all the transactions listed above, did not bring the expected result.