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30 Chapter 3 Hardware Troubleshooting
4Check for a dial tone.
5Use this extension to make a call to another extension on the system.
6If the expansion unit has an MBM that supports lines, go to an extension that has access to one of the lines on the MBM.
7Select the line or line pool to which the line belongs.
8Check for a dial tone.
9Make a call using the line or line pool.
To troubleshoot the expansion unit
1Check that the correct feature for the expansion unit is included in your installed keycode.
2Check that the expansion port is connected to the proper connector.
3Check the wiring to the MBM. Make sure that the cables are properly seated and are connected to the correct ports with proper LED indications.
4Check that the switches on the MBM are all set to on.
If the MBM is a GASM or GATM, all the switches on the right are not on.
To check the MBM switches, you must remove the MBM from the expansion unit.
5Perform a firmware download to ensure that the correct version is loaded on the ASM/GASM or GATM unit.
6Use Element Manager or Telset Admin to check the programming for the lines or extensions connected to the MBM.
7Reboot the system to ensure that the BCM450 main unit functions correctly.
8If the programming is incorrect, use the Backup and Restore Utility to load a recent backup of system programming. If a recent backup is not available, correct the programming using Element Manager or the Telephone Administration feature.
Testing an MBM
Use the following procedure to test an MBM installed in the main unit or expansion cabinet.
If you are experiencing an issue with an FEM, ensure all DIP switches are set to the On position.
Procedure steps
Step Action
1Check the Power and Status LEDs on the MBM. Both LEDs must be solid green. If either LED is not solid green, a problem exists with the MBM.
2Go to an extension on the MBM if it is a station MBM.
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