The expansion module can boot up normally, but it can’t be recognized by phone. When you login into web interface-> status page of the phone, there is no expansion information displayed in phone web interface.
The EXP cord is broken, software problem, hardware problem
1. Try another good EXP cord to exclude the EXP cord problem.
2. If the expansion module information isn’t displayed in web interface and it can’t work normally, please try to upgrade Expansion module.
Upgrading guide: http://forum.yealink.com/forum/showthread.php?tid=1414
3. If the problem persists, it should be a hardware problem, please contact your vendor or local distributor and send test result for help.
4. If you can’t get support from your vendor or distributor, then please send the problem description, test result of above steps, your country, phone SN number to ticket.yealink.com.
