Brand: SIEMENS
Category: Telephone
Document Type: Manual
Language: EN
Available Languages: EN , ES
Manual for C455
Uploaded: Nov. 21, 2025, 8:26 p.m.
Manual Publish Date: 2007
Warranty Information
No specific warranty period is mentioned in the extracted pages.
The handset at a glance
1 Display in idle status
2 Battery charge level
3 Control key
4 Display keys
5 End call key, On/Off key
6 Message key
7 Hash key
8 Alarm clock key
9 Microphone
10 Recall key
11 Star key
12 Connection socket for headset
13 Handsfree key
14 Talk key
15 Signal strength
Base station C455 at a glance
1 Registration/paging key
2 On/Off key
3 Delete current message
4 Skip to previous message
5 Adjust volume
6 Playback/Stop key
7 Skip to next message
Troubleshooting and error codes
| Problem | Possible Solution |
| The display is blank. | 1. The handset is not switched on. Press and hold the end call key. 2. The battery is flat. Charge the battery or replace it (page 6). |
| The handset does not respond to a key press. | The keypad lock is activated. Press and hold the hash key #º (page 11). |
| Base is flashing in the display. | 1. The handset is outside the range of the base station. Move the handset closer to the base. 2. The base station is not switched on. Check the base station mains adapter (page 5). |
| Handset does not ring. | The ringtone is switched off. Activate the ringtone (page 27). |
| You cannot hear a ringtone/dialling tone. | Base station's phone cord has been replaced. When purchasing a new cord, ensure that it has the correct pin connections (page 5). |
| The incoming call number is not displayed although CLIP (page 10) is set. | Phone number identification is not enabled. The caller should ask his network provider to enable Calling Line Identification (CLI). |
| You hear an error tone when keying an input (a descending sequence of tones). | Action has failed/invalid input. Repeat the operation. Watch the display and refer to the operating instructions if necessary. |
| The calls list does not indicate a time for a message. | Date/time are not set. Set the date/time (page 7). |
| The answering machine will not record any messages. | Its memory is full. Delete old messages. Play back new messages and delete. |