Yesterday, my best friend Allie Moore asked me if I could fix her computer. Of course, I accepted the offer. The computer would not run on AC power, but it will charge (slowly) if it is turned off.
The tools I brought are a Kill-a-Watt, a multimeter, a pair of "swiss army pliers", a set of screwdrivers, some soldering equipment, some electrical tape, and a 25w, 8.2 ohm resistor.
The problem was a bad connection in the plug. How I noticed it was that the Kill-a-Watt was always showing very low power draw at all times. Oddly enough, the multimeter showed full voltage at the plug. Out of curiosity, I decided to try load testing with the resistor. The voltage dropped by about half and the plug immediately got hot. I used the pliers to cut back the plug, exposing the connections. I resoldered them and it worked perfectly, after which I insulated the connections with electrical tape. I used the Kill-a-Watt to confirm that the power supply was indeed working.
I bet many students were wondering what was going on when I was sitting with a pretty girl, in the middle of the study lounge taking apart a laptop, using some unusual tools, and saying a lot of technical terms. Knowing how I am well known for my engineering, many probably thought I was training her to be a computer technician or something.
She also had another power supply that was broken for a long time. I currently have it on my desk. It appears completely dead as far as the output goes, but an AM radio shows that something is still working inside and the Kill-a-Watt indicates an unsteady current draw. I have just opened it and noticed some bad capacitors. Sometime later, I will replace those capacitors and test to see if it works.