https://stream.echo6.co/videos/watch/eff10a2c-46dc-4e6f-82a1-21fc05f9a68d How to test a computer transistor driver with a basic test light. This test is especially valuable when you have a faulty solenoid and cannot rely on voltage readings when the circuit is energized. Also this is the fastest way to verify wiring integrity of the control wire. A manufacturer flowchart will have you disconnect the computer and solenoid, then measure for opens and shorts with an ohmmeter. It's absolutely ridiculous that this is the standard method of testing a circuit! Suggested test light for this application is an LED type test light. Before performing this test, you must know what polarity to connect the test light to. Watch this video to determine circuit design How to test a computer controlled solenoid (power/ground side identification) https://youtu.be/kQz3g4HIWgs, Tests shown how to test a computer driver, how to test the control wire for opens and shorts, how to force an output driver to turn on without a scan tool, how to force an EGR solenoid circuit to turn on, Tools used Incandescent test light, Related videos How to test a computer controlled solenoid (circuit ID with voltmeter) https://youtu.be/pkcwNkkNWYA, How to test a computer transistor driver (using a scan tool) https://youtu.be/MOSH8XLKrLc, How to test a computer controlled solenoid (power/ground side identification) https://youtu.be/kQz3g4HIWgs, Playlist (Chapter 3) Transistors, Solenoids, Computer Controlled Output Testing https://www.youtube.com/playlist?list=PLE9BA8CBD51B8C48E, For more information on this topic, I have written a “field manual” called Engine Performance Diagnostics which is available at www.scannerdanner.com as an eBook or paper book. Want even more diagnostic training? Whether you are a DIY trying to fix your own car, someone looking to become an auto technician, or a current auto technician that wants to get more into diagnostics, subscribe to ScannerDanner Premium https://www.scannerdanner.com/join-scannerdanner-premium.html There is a 14 day free trial. On ScannerDanner Premium I will bring you right into my classroom at Rosedale Technical College. You will find page for page lectures taken right from my book as well as exclusive classroom type case studies. What is so special about these classroom case studies? I pull live problem vehicles directly into my classroom and we troubleshoot them in real time, using and applying the theory and testing procedures we learn during the classroom lectures. There is no better on-line training of how to troubleshoot automotive electrical and electronics systems anywhere! Disclaimer: Due to factors beyond the control of ScannerDanner LLC, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. ScannerDanner LLC assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. ScannerDanner LLC recommends safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond the control of ScannerDanner LLC, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user and not ScannerDanner LLC. Mon, 04 May 2026 01:23:32 GMT https://validator.w3.org/feed/docs/rss2.html PeerTube - https://stream.echo6.co https://stream.echo6.co/client/assets/images/icons/icon-512x512.png https://stream.echo6.co/videos/watch/eff10a2c-46dc-4e6f-82a1-21fc05f9a68d All rights reserved, unless otherwise specified in the terms specified at https://stream.echo6.co/about and potential licenses granted by each content's rightholder.