1120 phone showing "cable is unplugged"

[moggers]

Hello, I have hesitated before posting this question as it seems a bit simple. however I don't have an answer and so it's not that simple to me
We have a couple of phones showing "cable is unplugged" now the bizarre thing is that in order to get power to display this they must be on the POE cable hence the cable isn't unplugged. I feel this may just be a bad message for something else like no IP or something. Can anyone help me understand the problem so that I can remove the message and configure the phone.
Please note that I'm not on site so I can only doing things directly to the phone when help is willing
Thanks

 

[gwebster]

There was a problem with some of the older firmware where it would inadvertantly show this message in case of a duplex mismatch. So check that i) there is no duplex mismatch and ii) you are running latest firmware.

 

[biv343]

I've seen that issue when there are cabling problems such as homemade patch cords, poor terminations and things like that. I'd take the phones that are giving you issues and plug one directly into the data switch. If it works there, then you have a physical cabling problem between the phone location and the data switch. It could be as simple as a bad patch cord.

 

[bigindian65]

i get it when using to many ports on a PoE switch because you cant use them all.

Mato' Was'aka

 

[moggers]

Guys, thanks for the valuable suggestions. We'll be up on site soon (hopefully tomorrow) so I'll test all these suggestions.
I'll update the thread once we resolve this issue.
Thanks very much