Cisco VoIP - Basic Troubleshooting for Desk Phones
Basic troubleshooting steps for issues with a Cisco VoIP desk phone. Should be used for issues like being unable to place calls, screen is not functioning, phone is frozen, etc.
- Unplug the phone from power, wait 5 seconds and plug it back in.
- Check the power source.
- Is the power cable plugged into the wall?
- Check the connection between the power cable and the power cube, this can become loose. (Note, this is located between the phone and the wall)
- Is the power cable plug securely into the back of the phone?
- Check the Ethernet connection. Cable configuration should be data jack to phone to computer.
- Is the cable plugged securely into the wall jack?
- Is the cable plugged securely into the network port (3 box symbol) on the phone? The cable should lead from the wall port directly to the phone.
- Is the cable plugged securely into the computer? The cable should lead from the PC port (1 box symbol) on the phone directly to the computer.
- Are any of the cable connections loose or poorly fitted? The cable should not be jammed into a jack but it also should not be wiggly. Old cables are a common issue. If you can hold the cable a “certain way” in the jack and the Ethernet reconnects this is an indicator of a bad cable. If this is a problem, please replace the cable.
- Check handset cord.
- Is the handset cord securely plugged into the handset and back of the phone?
- Is the handset cord plugged into the handset port?
- Do an Admin Reset
- 7841 Phone
- Press the Applications button (looks like a gear)
- Press Settings
- Choose Device Administration
- Choose Factory Reset
- 8851 phone
- Press the Applications button (looks like a gear)
- Choose Administrator Settings
- Choose Reset settings
- Choose Reset Device
- Factory Reset (8851)
- Remove the power cord
- Wait 5 seconds
- Press and hold # while plugging the phone back in. Hold # until the headset and speaker buttons are lit.
- Enter the following key sequence: 123456789*0#
- Wait while the phone resets.
- If none of these fix your problems, please contact the DoIT Help Desk. Please be ready with the following information
- The MAC address of the phone Cisco VoIP - How to find a MAC address
- The model of the phone.
- The room and building where it is located.
- The jack number where it is plugged in.