This works Perfect. My wife's Escalade kept blowing the fuse for the rear back up camera. The dealership couldn't tell me for sure how much it would cost to fix as it was an hourly rate and searching out the electrical problem could take 1 hour upto 8 hours. I bought this and anxious to try it out, I went to the main harness and began to go forward. After passing another harness that fed off of the main line the needle started pointing the other way so, I knew I had passed the short. Went back to the other wiring harness and it just kept leading me directly to the short. I couldn't immediately see the short as it was on the bottom side of a wire resting on the alternator. Once I picked the wire up and saw the wear, I taped it, replaced the fuse and it worked. No other problems. This $32 tool and 5 minutes saved me money and the biggest thing... It saved the inconvenience of leaving my wife's car in the shop until it could be fixed. Highly Recommend this Gadget.This little tool helped me a lot to find my electrical problem, but not in the way intended.My tail light fuse kept blowing out every time I put one in. I tore up my dash and trunk trying to find the problem, and couldn't. I bought this tool.The tool works in place of a fuse, and allows current to flow for a few seconds before shutting off. It resets after several seconds, and current flows again. This feature allowed me to determine that my tail lights did not have a short, because the lights came on when the current flowed. The problem was a defective bulb in my parking light in the front of the car.So, the tool didn't find a short, but it allowed me to run current and see the problem was not a short to my tail lights.The short finder gauge is confusing, and the instructions on the gauge are contradicted by the written instructions. There is nothing in the instructions that explains that the current is not always flowing -- we heard some clicking, but only realized the thing was tripping when the tail lights would come on and then go off. The gauge can only work while current is flowing, so it would be nice if the instructions made this clear. Also, to use in place of a mini fuse, you have to break an old fuse to get the metal tabs out, clip the tool's leads onto them, and then insert them in the fuse box. Clumsy. Surely they could come up with a simple adapter that would make this easier.Still, I would not have solved my problem without this tool.Saved the day and hours of troubleshooting time. Loved the item and the priceI prefer the Power Probe ECT2000 Short Open Circuit Detector to this one. Both accomplish the same task. Neither is really user friendly, but just help with your troubleshooting.This short finder works. it tells you the direction of the ground using the needle. The ECT2000 has an arrow light that tells you the same thing along with a beep if there is current flowing.For me, I was frustrated finding an intermittent short. I found out afterwards that the short only happened while turning the steering wheel in my car. In this circumstance I found a light bulb that had no current so I hooked up the ECT2000 to the light bulb socket, and traced how far the current would go backwards. The SG tool aid couldn't help me at all, but the ECT2000 could.Granted, the ECT2000 is much more expensive, so if you have a constant short or a fuse that blows right away after replacing, this is what you need.Helps me get to the area of a short circuit quickly.It works. I wish it was a little more/less sensitive, and by that I mean I wish it gave more obvious reactions to a short vs just regular background juice sometimes. In some spots I was getting pretty weak reactions out of it for stuff that I believe was shorted out. It would be nice if it pulsed quicker as well so you didn't have to wait so long in between tracing the wire. That said it's pretty affordable compared to some of the fancy ones out there that do essentially the same thing, so I can't complain too much. At the end of the day for my particular repair the "what isn't working, and what wires go to that" method ended up working better for me... That said I'm pretty sure I found a couple minor shorts I didn't even know about, and I'm sure in different situations in the future it will be more useful for me.This short tester saved the day and a few hundred dollars in service on my Ford truck. I had a very difficult to find short on my truck. I used a fuse socket adapter, which makes it easier to attache the circuit breaker included with the tester to the fuse box. The circuit breaker takes the place of the fuse for testing, I tracked down the the hidden short within a half hour by moving the ammeter over the wires associated with that fuse. The meter fluctuates left to right, and centers over the suspected short. Turns out that I had a loose wiring loom rubbing against a brake line. Over time the brake line wore through the loom and into a wire associated with the speed sensor. The intermittent shorting of this wire cause my speedometer to stop operating and my transmission to stop shifting. A few repair shops told me that my transmission was bad, this was not the case, after the short was fixed I had no further transmission/speedometer issues.