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Intercom Troubleshooting Questions

Are you having trouble communicating through your intercom? Or, do you need help with fixing a loud noise on your device when selecting another station? Often, problems like these lead to questions that cannot be answered without an outside help. When such is the scenario, knowing where to find quick reliable solutions is usually the best recourse.

Read below where Experts online have given answers to intercom troubleshooting questions.

How to fix a NuTone intercom system that suddenly quit working due to an electrical failure?

Case Details: The message ‘IC’ appears on the screen with all the indicator lights on.

This usually occurs when there is a problem in sending and receiving control signals from the remote station to the master station.

  • First, turn off the remote power switch and the tuning switch located on the master station.
  • Then, look for the small hole beside the ‘Memory Set’ button at the lower front right side of the master station.
  • Next, insert a pin into the hole and press the recessed button.
  • Finally, release the button and the display should return to the normal time to let you reprogram the time and radio station.

How to disconnect the intercom system on a Sony cordless phone?

  • Put the handset in the base unit.
  • Then, unplug both the power and phone lines from the base unit.
  • Leave the unit untouched for five minutes.
  • Next, reconnect the phone and the power lines to see if it solves the issue.

If it does not:

  • Take out the battery from the handset.
  • Then, unplug the phone lines and the power lines again from the base station. Make sure to separate the handset from the base station before doing this.
  • Next, wait for 15 minutes and reconnect both the power and phone cords.
  • Finally, place the handset in the base for a minute.

If this still does not fix the problem, then it would either indicate a memory failure or a stuck intercom button that will need to be further diagnosed to figure out the true fault.

How to repair an M&S intercom system MC350A that fails to turn on with a message ‘List’ on the display?

  • First, disconnect the unit for an hour.
  • Then, reconnect to turn it on. This will reset the processor and allow the unit to operate normally.
  • Additionally, inspect the speaker wiring for any shorts. Make sure they are not coming in contact with the chassis of the receiver.
  • Finally, unplug all the speakers and cycle the power off and then on.

If the unit appears to shut down with all the speakers disconnected or does not power up, then the fault could be with the output transistor or the capacitors that will need to be further checked for a proper diagnosis.

What can be done if the monitor on a video intercom fails to communicate with the door station?

  • First, make sure the power supply on the unit is set to either 12VDC or 24VDC.
  • Then, disconnect the magnetic lock wires and check the power wires for any shorts.
  • If there are no shorts, inspect the magnetic locks for any faults.
  • Finally, verify if the jumpers on the locks are set to 12VDC or 24VDC.

How to fix an Aiphone intercom that makes a loud noise when selecting another station?

  • First, verify if the handset and the cord are working fine.
  • If so, inspect the microphone and the speaker for any faults. Most often, an incorrect termination of the speaker or the microphone can likely cause this to happen.
  • Simultaneously, check if the handset has been dropped to ensure it’s not causing the issue.
  • Next, perform a continuity check on the lead terminal to see if it’s working fine.
  • Then, test the microphone with an oscilloscope along with checking the speaker with a tone generator.
  • Finally, if all of these components appear good, inspect the main board for any issues. An imbalance in the audio circuit or a fault in the side tone path can also cause this issue.

If the problem still continues, the unit itself is faulty and will need to be replaced.

How to restore a home intercom system to normal mode that keeps flashing ‘Time’ constantly on the display?

  • Press the ‘Time/Auto Set’ button to indicate the option ‘Set Time’ along with displaying the current time with the hours flashing.
  • Use the ‘Up’ or ‘Down’ buttons to increase or decrease the current time hours.
  • Next, press the ‘Time/Auto Set’ button again. This will display the option ‘Set Time’ along with indicating the current time with the minutes flashing.
  • Use the ‘Up’ or ‘Down’ buttons to increase or decrease the current time minutes.
  • Finally, depress the ‘Time/Auto Set’ button for a couple of minutes to allow the unit to return to normal mode. Alternatively, the unit will return to the normal mode automatically in nine seconds, if no buttons are pressed.

In case none of these procedures work, then check the electronic contacts below the button for any faults and replace, if necessary. However, before doing this, cleaning the contacts will be strongly recommended.

Has it ever happened to you that you had to answer the door to an unwanted visitor? If so, then owning an intercom system can help serve you the best. It not only wards off uninvited and unannounced visitors from your house but also ensures security from potential criminals. Thus, it is highly recommended to keep these units in working order to maintain peace and comfort in the house. However, these units can often go bad causing a huge trouble to its users. When this is the case, contacting an Expert immediately for repair is strongly advised. Verified Experts are readily available to help fix your issues at your earliest convenience anytime day or night.

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