⚡ Do you want to be a successful electrician? Check out my complete training. Click here ???????? https://www.eunaupmotors.com.br/eletr... --------------------------------------------------------------------------------------- The automotive electrician must always be equipped with good tools to be able to work more accurately and quickly as possible because the more services delivered, the more money in your pocket. Today we are going to talk about a multifunctional, versatile tool that can be made at home. This is the test pen with signal injection, it is used to analyze the polarity of a wire and also send a positive or negative signal to its test tip. With this tool we have a wide range of testing and activation possibilities without having to connect other wires externally to perform a test activation to find out if a component is working properly. To make this tool you will need the components of a conventional polarity test pen which are 2 LED, 1 common diode, 2 1000 hom resistors, 2 connection alligators for signal collection and one meter of double speaker wire. In addition to these, we will need the components for the signal injection part, which are: 1 3-touch on/off/on switch, 1 old relay so that we can use only the plastic box, an old multimeter tip and a fuse holder with a 5ah fuse. We make the normal connection of the common polarity test pen and then we take the 3-touch switch and check below it that it also has 3 connection pins, on one of the pins at the end we connect 1 wire directly to the main input positive and on the other pin at the end we connect the negative, the middle pin of the switch we connect to the test lead, but in the middle it will be necessary to place the fuse holder to protect the switch from any possible short circuit. If it does not have the protection fuse, the switch will burn out if you accidentally connect the test lead to a wire that has the opposite polarity to that being sent by the switch. After making all the connections for the test circuit on the bench and if everything worked, then it's time to assemble everything inside the relay box. Here, everyone does what they think is best. I thought it would be interesting to place the switch and the LEDs facing the top of the relay box so they would be more visible. I placed the fuse on the side, also facing the back, and on the opposite side, I placed the test lead and the output of the pair of wires with alligator clips to connect to the positive and negative of the car. I left this pair of wires from my pen at 1 meter, but you can leave it as long as you want. After everything is assembled, just use it to test the polarity of the wires and to perform tests when you need a positive or negative signal on a component. I hope you enjoyed this tool and if you have the possibility to do it, I'm sure it will help a lot in your day-to-day work and in diagnosing electrical defects in cars. Thank you for following along so far and I'll be waiting for you with our next topic, thanks. Complete Courses, all in one place! I teach you with the best current techniques, with my method that has already been tested and approved by more than 2,600 students in Brazil and other countries. The most complete course in Brazil, without any fuss. I know what works in practice within a workshop and I will teach you in a simple and online way, from basic to advanced. You will learn, even if you have no knowledge, until you perform the services just like the best professionals you know. ⚡ Successful Electrician. Click here ???????? https://www.eunaupmotors.com.br/eletr... ???? Car Sound System Installer. Click here ????????https://www.eunaupmotors.com.br/insta... ---------------------- ▶ SUBSCRIBE TO THE CHANNEL / upmotorscentrodeforma%c3%a7%c3%a3oautomotiva ---------------------- ????FOLLOW ME ↴ ▶ Facebook: / eunaupmotors ▶ Instagram: / eunaupmotors ▶ Telegram: https://t.me/Eletricista_UpMotors ▶ Website: https://www.eunaupmotors.com.br/