A friend of mine brought this hairdryer with a complaint that it does not work and that possibly there is a broken wire because the external insolation of the cable was broken in one place.
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Start with a visual inspection
Any repair starts with a visual inspection first so we can familiarize ourselves with the issue and try to spot any obvious issues. For this, I first inspected the pointed-out area of the cable for any broken wires, but even though the insulation was damaged, the wires looked OK.
When I plugged the hairdryer into the outlet, I noticed that the status LED was dimly glowing so I thought that the issue must be inside with some of the components, so I opened it inside.
Tools and materials
A list of tools and materials that I commonly use in my repairs. If you purchase through the links below, you are helping me and my channel at no extra cost to you!
- Precision Screwdriver Set - https://s.click.aliexpress.com/e/_mOdGOLa
- Multimeter - https://s.click.aliexpress.com/e/_EwwvqFT
- Soldering Station - https://s.click.aliexpress.com/e/_EILy42h
- Bench Power Supply - https://s.click.aliexpress.com/e/_EI0dsSZ
- Assorted Components - https://s.click.aliexpress.com/e/_msyreRi
- Wire Snips - https://s.click.aliexpress.com/e/_EvdiCr7
- Dim Bulb Tester - https://www.youtube.com/watch?v=CCI01FqjV9I
- Professional Hairdryer - https://s.click.aliexpress.com/e/_EviSv3R
Open up the hairdryer
In this particular version, they did a very good job of hiding the screws. There we two pink plastic pieces on the sides of the handle that we each hiding a screw, and there was a ring piece in the bottom of the handle, where the cable enters that was hiding another two screws.
This was held in place with some clips and after applying some force with the help of two screwdrivers, I managed to release it, remove the screws and get access to the inside of the hairdryer.
Inspect the wires
Having access to where the wires connect on the inside, the very first thing that I did was to check them for continuity with my multimeter. Since we had some damage to the insulation of the power cable, it was quite possible that there was some issue and it turned out that I was right but not in the way I thought.
One of the wires was broken but it was the blue wire and not the brown that was close to the broken outside insulation.
Since I now knew that some replacement was needed, I cut the cable where it was damaged, and when I tested the blue wire from there, it turned out that it was broken next to the plug while the rest was OK, so a new plug was needed.
Add a new plug
I found a salvaged plug in my parts drawer but they are also very cheap to be replaced with a new one so I proceeded to strip the insulation from the wires, twisting them together and soldering both so that they make a nice and solid connection.
I added heat-shrink tubing to the wires and I used a bunch of electrical tape to add some strength to the cable.
Reassemble and test
Lastly, before I put everything together, I made sure to test the wires with the multimeter, and to also test the hairdryer that it now worked as expected.
This turned out to be a simple repair and since I used a salvaged plug it was also free and the hairdryer can be removed from the dumpster for at least some time more.
