FRITZ!Box 7490 Service - Knowledge Base
FRITZ!Box reports "Interference may have been caused by powerline"
The FRITZ!Box's VDSL connection drops frequently as soon as powerline adapters connect to the FRITZ!Box. When this occurs, the "Power" LED on the FRITZ!Box flashes and stays lit as soon as the internet connection has been reestablished. The following error message is displayed in the event log of the FRITZ!Box:
"The internet connection (DSL) was cleared. Interference may have been caused by powerline."
- Powerline is disturbing the VDSL connection. Since the frequencies used by VDSL and powerline partially overlap, both technologies can interfere with each other.
Note:All instructions on configuration and settings given in this guide refer to the latest FRITZ!OS for the FRITZ!Box.
Simply proceed as described below. After each measure, check whether the problem persists.
1 Checking the cabling
- Plug the powerline adapter directly into a wall outlet. Do not use a power strip or an extension cord.
- Lay the DSL cable at a distance of at least 10 cm away from electrical wiring and outlets. The greater the distance between electrical wiring and the DSL cable, the better.
- Do not roll cables and avoid loops in the cables ("cable spaghetti").
- Test whether you can solve the problem by positioning the powerline adapter connected to the FRITZ!Box farther away from the DSL connection. For example, plug it into a different wall outlet.
2 Running malfunction detection
- Click "Internet" in the FRITZ!Box user interface.
- Click "DSL Information" in the "Internet" menu.
- Click on the "Interference Resistance" ("Line Settings") tab. If the tab is not displayed, enable the Advanced View first.
- Click on the "Detect and Resolve Malfunctions" button. Now the FRITZ!Box checks the powerline connections and attempts to resolve problems with the the DSL connection.
- If the button "Detect and Resolve Malfunctions" is still shown after running the test, repeat the test until no further improvement of the DSL connection is possible.
- When you have finished testing, click "Finished".