Mitel Panther II 820 System Manual page 257

Trillium Standard Practise
Note: If the data pair is reversed, the Panther set telephone will not function properly.
For Peripherals and Optional Equipment:
Use the procedures outlined in
Panther II 820/1032l2064-320, Maintenance and
Troubleshooting
to perform a system check on peripherals and options such as Station
'
Message Detail Recording.
Installation and Commissioning
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