If no ink comes out but you can hear that the pump is working
(when the pump is working, you will hear the buzz sound go on
and off continuously). You can press the “Left” button and the
carriage will move out (to set up starting position of printing),
you will see the ink cap exposed, use a syringe (and you can put
a short ink tube in front to make the process easier) to pull
some cleaning liquid and squeezes into the ink cap until almost
full. Then restart the pump, if you see the liquid come out to the
waste ink bottom (you can also confirm this by move carriage
away again and all liquid in cap will be gone), then we say
bottom part is fine, otherwise not.
If the Bottom Part is not Working:
If you can hear the ink pump emitting a pumping sound but see
that there still is some liquid in the ink cap, the first possible
situation is that the ink pump itself is stuck, because ink might
dry inside as well. As much as electricity may pump it but the
ink inside the tube will not move. To test this, you can remove
the cover and you will see the pumping action, remove the tube
from the pump and when the pump is working, you can use
your finger to feel it sucking or blowing depending on which
side of the tube that you removed. The Ink pump can be opened
and washed, or simply replaced. It is a cheap component.
If the pump is working but there is no flow, then there are two
probable situations, the pump is either blocked by the dry ink, or
leakage of air between the Ink Cap to the Ink Pump. Those
tubes can also be replaced, or you can wash them by syringe
and cleaning liquid.
If the Top Part is not working:
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