Bosch Tassimo Hot Drinks Machine

Bosch Tassimo Hot Drinks Machine Repairs | Tassimo Hot Water Dispenser | Forum

Has your Bosch Tassimo Hot Drinks Machine suddenly stopped working? It may well be repairable.

The Problematic Cap

A friend's Tassimo (Model number TAS4011GB/03) recently went "BANG!" and smoke rose from inside. I wasn't hopeful it could be repaired but it turned out to be a little cap inside which had popped up which was causing water to spray all over the inside during the brew cycle. Water and electricity do not go together and so BANG! Re-secure the cap back in place, dry up any water left inside, and everything works fine again.


Arrow points to problematic cap with cable tie added.
The location of the problematic cap is shown in the diagram to the left. It is held in place by two lugs. Perhaps these separate over time and eventually flex to allow the cap to spring open... BANG!

Hopefully either the fuse in your Tassimo's plug blew or your home's circuit breaker tripped before serious damage was done inside the Tassimo. If so, you can reposition the cap and secure it in place with a small cable tie and your Tassimo will be as good as new!

The hardest bit about the repair is getting inside the Tassimo. I don't think Bosch intend for there to be any user-serviceable parts inside. There are no screws to undo - you just have to pop both sides off.

Replacing the problematic cap


Right side of machine (when viewed from front),
with side panel removed, fixings circled.
  1. Unplug your Tassimo
  2. Remove the loosely-attached parts such as the water reservoir and drip tray.
  3. You should now be able to pick your Tassimo up. A little water may drip out. Just mop it up.
  4. Both sides of your Tassimo need to be removed. There are no screws. Try to slide each side towards the back of the machine to disengage it from it's fixings (circled in diagram). You might need to use a medium-sized flat bladed screwdriver and be a bit forceful.
  5. Once both sides have been removed, use the screwdriver again to spring the 4 clips which hold the entire top assembly of the machine in place.
  6. You should now be able to move the top assembly slightly to get to the problematic cap beneath.
  7. Carefully remove the cap and reposition the small filter and O-ring which resides underneath.
  8. Replace the cap and try to secure it beneath the two lugs. I used a small cable tie wrapped around the opposing lugs to try to stop them springing apart again. See photo below.

    Close up of cap with added cable tie in place.
  9. Reassemble, allow the inside of your Tassimo to dry out if required before powering up. I'd recommend you plug your Tassimo into a power outlet via a portable RCD device if your house is not already protected by one.

No green light after inserting T-disc

This could be caused by one of two things. Both are easy to check. Turn on your Tassimo machine.

Firstly, lift the lid and check that the barcode reader is not dirty or cloudy. If it is, your Tassimo will not be able to read the barcodes on T-discs and this will prevent the green light from appearing. People have told me a number of ways to clean a dirty barcode reader. If just giving it a wipe doesn't work, try smearing a little cooking oil on it and see if that help. Failing that, another suggestion was to give the barcode reader a little clean with toothpaste!


Microswitch (arrowed) under lid on left (when viewed from front).

Secondly, look under the lid, on the left hand side (when viewed from the front) and you will see a small black piece of plastic protruding (see photo). This bit of plastic is pushed back when the lid is closed and presses a microswitch underneath. Sometimes, the microswitch can move slightly which prevents it from detecting when the lid is fully closed which can again, prevent the green light from appearing.

To test the microswitch gently push the protruding bit of plastic (arrowed) back. You should feel a little movement and hear a click from the microswitch. At the same time, the barcode reader should light up red. If it does not, the microswitch has probably moved. It can easily be repositioned after opening up your Tassimo as described above.

More Information

Please let me know if you have any comments.