FRITZ!Fon C5 Service - Knowledge base

FRITZ!Fon C5 Service
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FRITZ!Fon does not turn on

The FRITZ!Fon can no longer be turned on. When you try to turn on the telephone, the message key and end call key light up red, but the display remains black and the telephone does not work.

Simply proceed as described below. After each measure, check whether the problem persists.

1 Charging the battery

  1. Plug in the charging cradle. Make sure that both plugs on the charging cable are inserted correctly.
  2. Leave the telephone in the charging cradle for at least 6 hours to completely charge the telephone's battery. Make sure that the telephone is resting correctly in the cradle.

2 Checking the battery

The FRITZ!Fon's battery may be defective. There are two different ways to check the battery:

Testing a different battery

If you have another FRITZ!Fon with the same type of battery, try using the other battery for testing purposes:

  • Fully charge the other battery and insert the battery into the telephone.

If you can turn the telephone off now, then the other battery is defective.

Turning on in charger cradle while battery is removed

  1. Remove the rechargeable battery from the telephone.
  2. Place the telephone into the charging cradle without its battery inserted.

If the telephone can be turned on while in the cradle, then the battery is defective.

3 Replacing the rechargeable battery

You can purchase a genuine replacement battery from an electronics retailer. Using so-called aftermarket batteries that are not originals, like the kind available over the internet, may damage your FRITZ!Fon.

Important:Rechargeable batteries wear out because they are subject to a natural aging process as physical and chemical changes occur within the battery; this is why they are not covered by the warranty (see warranty in the manual).