CP-7914 Expansion Module was connected by a long cable (not sure of the length) - RJ11 straight-through cable to the CP-7960G phone and the customer claims that this was working before and all of a sidden stopped working and the CP-7914 show all RED LEDs.
Anyway we sent a tech to site and while troubleshooting he used a short RJ11 (18 cms. long) cable and it all started working.
Is there a specification on the cable length that one can use with this device. Don't ask me why the customer is using a long cable and keeping the CP-7914 far away from the CP-7960G IP phone.