How to troubleshoot a starting system (bad ignition switch) - Dodge Neon

This case study I did on a body shop vehicle covers a lot of starter circuit theory and operation, as well as practical testing methods, making it great viewing for anyone working in the field. Even though the subject is a Neon, the information I cover will apply to all starting systems and standard relays. I also get to show the power of a simple test light, and how valuable it can be in electrical troubleshooting.

Engine Performance Diagnostics chapter 3

Symptoms
engine does not crank
“FUSE” message on dashboard

Fix
replace faulty ignition switch

Tests shown
using a wiring diagram to analyze a starter circuit
how to determine if a circuit is power or ground side switched
understanding PCM inputs for starter control
how to test for main power and solenoid power at the starter
how to verify your test light is making good power/ground contact
how to check a basic four pin relay with a test light
how to check an ignition switch for starter control
performing an ignition switch bypass with a test light

Tools used
lab scope (a simple DMM may be used)
incandescent test light

Playlist
(Chapter 3) Transistors, Solenoids, Computer Controlled Output Testing
   • (Chapter 3) Transistors, Solenoids, Comput...  

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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-sc... 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.