To get access to the switch assembly so that the mains wire can be disconnected, you have to remove the switch button. If you look closely along the flat edge of the switch button you will see a little notch in the surrounding plastic:
Insert the bent screwdriver into this notch and push down quite hard so that it goes down as far as it can.
At the same time, pull on the button so that it is "up" (in the off position) and push the screwdriver handle up. This should depress the catch that is holding the button in the housing and if you keep pulling the button up it should eventually come away. You will need to apply quite a bit of pressure to the screwdriver handle in order to depress the catch on the button.
After removing the button you will see the switch, spring and Torx screwhead that is retaining the switch assembly. Now you can see why the blasted thing will not come apart! 🙂
Using a T15 Torx screwdriver, remove the retaining screw.
After removing the screw, grab the cable grommet and slide it updwards. The switch assembly should then slide out of it’s housing.
The connectors should, I assume, be insulated with insulating housings, but only one of mine is, so someone’s been here before on my Dyson! (It was second hand when I bought it so maybe that’s not so surprising).
Slide the grommet out of the groove and pull it back to reveal the cable. In my case, you can quite clearly see the problem. I am really surprised this did not cause an electrical fire or blow a fuse.
Unplug the connectors for the mains lead and feed the cable round the bend so you can remove it completely from the switch. You can remove the other two connectors if you want to make this easier but I did it without disturbing the other connectors. A pair of snipe nose pliers might come in handy here.
Cut off the bad part of cable with some snips.
The outer insulation needs to be stripped, but to get the correct length, lay the cable off-cut alongside the mains lead and match up the ends. Strip the insulation away from the corresponding place on the mains lead. I use a sharp modeller’s knife to do this but you have to be very careful not to nick or cut into the insulation of the inner cables. So be very gentle and gradually cut away the insulation. The trick is to "press" onto the outer insulation rather than use a "sawing" or "cutting" motion. This is why you need a very sharp blade so that pressure alone is enough to cut into the outer insulation. If you nick the inner insulation so that you can see the copper core, cut off the cable and start again. Remember you are playing with 240V here so it’s not worth the risk of starting a fire.
Once you have stripped away the outser insulation, cut off some 1-inch lengths of heatshrink tubing and place over the cables – this is so that we can insulate the spade connectors (you can get heatshrink tubing from Maplins and Halfords – try and get an assortment so you get the right size – it needs to be big enough to slide over the connecters but small enough to shrink down).
Now strip away the insulation on the ends of both the brown and blue wires.
Fit a red spade connector (I got mine from Halfords)…
Now feed the cables back through the bend in the switch assembly – this is very important as it provides strain relief when you are yanking the cable about. You may want to push the heatshrink so that it is already half way over the spade connectors – my heatshrink was a bit tight so it was easier for me to do this first rather than trying to do it later.
Now reconnect the live (brown) wire first. Snipe nose pliers will help here as the connectors are quite hard to push on.
Use the snipe nose pliers to push the heat shrink over the spade connector to fully insulate it. Because mine was quite tight, it was quite difficult, and it chewed up the tubing a little, but it doesn’t matter what it looks like cosmetically!
As it’s shrinkable, you can use a soldering iron or heat gun to shrink the tubing if you want, but as mine was quite a tight fit anyway, I didn’t bother.
Connect up the neutral (blue) wire and slide the tubing over the connector again.
If the other connectors are uninsulated, you could detach them and insulate those too.
Slide the cable grommet back up the cable and locate back in it’s slot.
Now it’s simply a matter of sliding the switch assembly back into the housing…
…doing up the retaining screw…
…and fitting the button.
Without the £2 bent screwdriver, this would not have been possible! 🙂