Cisco 7941 Dialtone Issues

cyoungblut · ‎06-19-2009

Hello all - having a strange problem here. We have had about 7 Cisco 7941 phones in the last week that have had problems getting dialtone when lifting the handset. They get a dialtone 100% of the time when hitting the speaker button. I have had CISCO TAC taking a look and they thought maybe the phone (when we thought we only had a couple with the problem) was bad. I find it strange that I have 7 with the exact same problem. We are running Cisco CallManager 5.1(1). any ideas - ever seen it before?

dennisbehrens · ‎06-19-2009

When you lift the handset, does the handset icon in the status bar (directly above the left-most softkey) show up?

If so, this is likely a hookflash button problem. You can try pressing the button rapidly for 50 or so presses, as they are supposed to be self-cleaning. If that doesn't work, you can replace them under Smartnet if you have it, or take the phone apart and clean it (this will void any warranty).

If the hookflash icon is showing up, it's likely a SCCP communication problem with UCM. You are either having a QoS problem, network performance problem, or UCM performance problem.

Rob Huffman · ‎06-19-2009

Hi Chris,

Just to add a note to the great tips from Dennis (+5 points Dennis)

I'm 99% sure its RMA time for these phone. This is most likely a problem with the Hookswitch. After deploying Cisco IP Phones for the last few years we (and many others) have found this to be the most common hardware problem. We have had many 7941/7961's die in the last month as well (not running CUCM 5.1). We have engaged our Cisco SE and CAM and we have sent a number of these phones off to Cisco for testing. This seems to be an inherent design flaw with the Hookswitch on these phones. I would encourage you to engage your Cisco reps as well, we have been told that this issue has been escalated to the Cisco Business Unit in charge of this product line.

There is a "Best Practice" for cleaning the Hookswitch contacts (link below) that does work on occasion. Usually the phone has to be replaced/RMA'd.

Best?? Practices for Cleaning and Troubleshooting Cisco IP Phone Hookswitch

From this interesting Tech note;

http://www.cisco.com/en/US/products/hw/phones/ps379/products_tech_note09186a00801c0810.shtml

Hope this helps!

Rob

cyoungblut · ‎06-19-2009

Thanks everyone for their assistance. That seemed to be the problem - phewwwww! that was a strange one and had me boggled. For the most part tapping on it for about a minute seems to help. On a couple I took them apart and cleaned with some compressed air to get them to operate properly. If continue to be a problem I'll talk to Cisco about RMA.

Thanks everyone!