Make sure that the amphenol connector to the 412TDL is wired correctly. Are you using a patch panel to connect phones to the 412TDL? If so, make sure that the wiring from the amphenol connector to the patch panel follows the correct color-code sequence in Avaya's documentation. Sometimes, people wire these things up incorrectly.
Tom Daugirdas,
President
STCG, Inc.
stcg.com