- Networks
- Cable gateways
POWER-CABLE-INTERMITENTE
FRITZ!Box POWER-CABLE-INTERMITENTE on cable router: not online
Risk level
Low
Usually safe to check without specialist tools.
Urgency
Medium
Quick answer
If the Power/Cable LED on your cable FRITZ!Box is still flashing after 20 minutes, it has not managed to connect to your cable provider. Check that the provider has unlocked it and inspect the coaxial cable to the Data socket.
Safety first
Stop and check this first
- Do not open the FRITZ!Box casing or tamper with the multimedia socket: only swap accessible cables and adapters.
- Only your cable provider can unlock the device: do not try to register it with details the provider did not give you.
Safe checks you can perform
- Wait the full 20 minutes
- Confirm the unlock with your cable provider
- Cable straight to the Data socket
- Test a different coaxial cable
- Restart from the FRITZ!Box interface
Leave these tasks to a qualified professional
- Do not attempt this professional task: Line check by the cable provider
- Do not attempt this professional task: Ask FRITZ! support about the model
What a technician must be able to justify
Technician visit
These are the steps they must carry out and show you. Tick them as they work: if steps are skipped, do not accept a part swap.
These are not instructions for opening or handling the equipment yourself. They are the checks that should support a technical conclusion.
Line check by the cable provider
What they doIf the LED still flashes with the device unlocked, direct cabling and another coaxial cable, your cable provider checks the device registration and the line signal.
They must show youthat the FRITZ!Box is registered on their network and the signal status at your socket.
In writingthe ticket number, the diagnosis and whether a technician visit is needed.
Ask FRITZ! support about the model
What they doIf the provider says your model is not compatible with their network, FRITZ! support confirms whether your device's article number works on that connection.
They must show youyour FRITZ!Box article number and its compatibility with your network.
In writingthe case number and the conclusion on compatibility or replacement.
Before accepting a part or repair
Nothing has been shown yet. Do not accept a part swap based on the code alone.
Follow these steps
Note: Follow the documented order. An error code identifies the affected system, but it does not prove by itself which part has failed.
Wait the full 20 minutes
- Who:
- you.
- How:
- after plugging in or restarting the FRITZ!Box, leave it untouched for at least 20 minutes and note whether the Power/Cable LED ends up solid.
- Result that matters:
- telling a slow first connection apart from a real fault.
- If the LED turns solid within 20 minutes:
- the connection with the cable provider is complete.
- If it is still flashing after that:
- check the unlock and the cabling.
- Evidence to keep:
- time you powered it on and time you checked the LED.
Evidence: The FRITZ!Box's Power LED flashes (FRITZ!Box 6690 Cable)
Confirm the unlock with your cable provider
- Who:
- you, with your cable provider.
- How:
- use the provider's activation portal or call their customer service; if asked, give the serial number and the CM MAC address printed on the FRITZ!Box type label.
- Result that matters:
- the provider confirming the device is registered on their network.
- If it was not unlocked:
- after activation, wait up to 20 minutes again.
- If it was already unlocked:
- move on to the coaxial cable.
- Evidence to keep:
- photo of the type label (serial and CM MAC) and the activation reference.
Evidence: The FRITZ!Box's Power LED flashes (FRITZ!Box 6690 Cable)
Cable straight to the Data socket
- Who:
- you.
- How:
- remove extensions and adapters and connect the included coaxial cable from the Cable socket on the FRITZ!Box to the Data socket on the first multimedia socket; if a technician installed the line, use their cable and socket.
- Result that matters:
- ruling out a cabling fault that is easy to miss.
- If the LED turns solid after a few minutes:
- the problem was the cabling.
- If it keeps flashing:
- test a different coaxial cable.
- Evidence to keep:
- photo of how the coaxial cable is connected.
Evidence: The FRITZ!Box's Power LED flashes (FRITZ!Box 6690 Cable)
Test a different coaxial cable
- Who:
- you.
- How:
- connect the FRITZ!Box to the Data socket with another coaxial cable, for example one from a different cable modem, and wait up to 20 minutes.
- Result that matters:
- finding out whether the previous cable is defective.
- If the Power/Cable LED turns solid:
- the previous cable is defective and must be replaced.
- If it still flashes with another cable:
- contact your cable provider.
- Evidence to keep:
- note of which cable you tried and the final LED state.
Evidence: The FRITZ!Box's Power LED flashes (FRITZ!Box 6690 Cable)
Restart from the FRITZ!Box interface
- Who:
- you.
- How:
- in the FRITZ!Box user interface open System, Backup, and click Restart FRITZ!Box; then wait up to 20 minutes for it to reconnect.
- Result that matters:
- forcing a fresh negotiation with the cable network without erasing settings.
- If after the restart the LED turns solid:
- the connection is back.
- If it goes back to flashing non-stop:
- the case goes to your cable provider.
- Evidence to keep:
- time of the restart and LED state after 20 minutes.
Evidence: The FRITZ!Box's Power LED flashes (FRITZ!Box 6690 Cable)
Still not solved
If the error persists, stop here. See what the technician must do and show you.
Where this code applies
A code is meaningful only inside the right product and version context.
Primary scope
- System
- Networks
- Brand
- FRITZ!
- Product type
- Cable gateways
Known code variants
- FRITZ!Box 6660 Cable no conecta a Internet
- FRITZ!Box 6660 Cable no internet
- FRITZ!Box 6690 Cable luz Power parpadea
- FRITZ!Box 6690 Cable Power LED flashing
- FRITZ!Box cable led Power/Cable intermitente
- FRITZ!Box cable luz parpadeando sin Internet
- FRITZ!Box cable provider unlock
- FRITZ!Box cable router LED blinking
- FRITZ!Box desbloqueo operador de cable
- FRITZ!Box Power/Cable LED keeps flashing
What it means
According to FRITZ!, when a cable FRITZ!Box (for example the 6690 Cable) is connected to the socket, it negotiates with the cable provider's network, which can take up to 20 minutes; meanwhile the Power/Cable LED flashes and then stays lit. If it keeps flashing after that and you have no internet, the link with the cable network was not completed: the provider has not unlocked the device, there is a cabling fault or a line problem. The LED alone never proves the FRITZ!Box is faulty.
Warnings and stop conditions
- Lowsource verified
Do not open the FRITZ!Box casing or tamper with the multimedia socket: only swap accessible cables and adapters.
Evidence: The FRITZ!Box's Power LED flashes (FRITZ!Box 6690 Cable)
- Lowsource verified
Only your cable provider can unlock the device: do not try to register it with details the provider did not give you.
Evidence: The FRITZ!Box's Power LED flashes (FRITZ!Box 6690 Cable)
Symptoms and causes
Probable causes · in order
- The provider has not unlocked the device yetCommon
FRITZ! says that if you bought the FRITZ!Box from a retailer, your cable provider must unlock it before it can connect.
Evidence: The FRITZ!Box's Power LED flashes (FRITZ!Box 6690 Cable)
- Extensions or adapters on the coaxial linePossible
The official guide asks you to remove all cable extensions and adapters between the FRITZ!Box and the multimedia socket, since cabling errors often go unnoticed.
Evidence: The FRITZ!Box's Power LED flashes (FRITZ!Box 6690 Cable)
- Defective coaxial cablePossible
FRITZ! explains that the cable linking the FRITZ!Box to the socket may be defective and suggests testing a different coaxial cable.
Evidence: The FRITZ!Box's Power LED flashes (FRITZ!Box 6690 Cable)
- Model not suitable for that cable networkLess common
FRITZ! warns that only the 6690 Cable with article number 20002965 or 20002995 works on every cable connection in countries with free router choice.
Evidence: The FRITZ!Box's Power LED flashes (FRITZ!Box 6690 Cable)
Virtual technician
Does POWER-CABLE-INTERMITENTE still appear after these checks?
Answer a few questions to narrow down the likely cause and the safest next action. Guidance only - it never replaces a professional.
Sources and technical references
- 1
The FRITZ!Box's Power LED flashes (FRITZ!Box 6690 Cable)
FRITZ! (AVM) · 2026 · official_doc
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