If you find no problems with the electrical supply and the switch, the next step is to investigate the motor assembly.

One of the most common causes of damage to the motor is fluid entering the pump system, which can affect both the pump mechanism and the electrical connections.

So the first thing to do is to check the pump assembly for continuity.

On some other devices, there are terminals where the power goes into the pump, where you would normally test for continuity, but on this device, the insulated wires from the switch go right into the copper coil.

So you first need to test the two black cables coming out of the switch, which then go to the pump. You would take these cables off to test for continuity through the pump.

There are several other tests you can do. So let’s have a look in a bit more detail as to how the electrical components in the pump fit together.

To do this, you may find it easier to take the pump assembly out of the device. It is not held in by screws, so it lifts out. You could then do the tests with a pump like this. That would be the easiest thing.

However, in this video, the pump assembly has been taken apart with the fan removed, so that you can see the different components more easily. We tell you how to take the pump apart in another video.

On the right side, there’s an insulated copper coil, which you can see here, protected by a white covering. Inside this coil, there is a safety switch which automatically turns off if the coil overheats for any reason. It will then turn on again by itself once the coil cools down. This could take up to an hour. So if you have a broken device where the coil is still hot, you need to leave it to cool down before testing the electrical circuits.

The copper coil and the iron core are separate from each other and are opposite poles. So if you test for the continuity between the exposed copper rings and the iron core like this, you should hear your multimeter bleep to show that there is continuity.

If, on the other hand, you test from one of the black cables on the switch to the exposed copper rings or the iron core, you should get no continuity.

This is because the black cable goes into the covered coil, which is a separate circuit from the iron core, and there should be no connection between them. If you hear a bleep, it means there is a short circuit.

The bottom line is that if these tests show an electrical fault within the pump motor assembly, then the solution is to replace the motor with a new one. Remember, these checks can usually be carried out without having to take the whole motor assembly out of the device.