GM Fuel Pump Relay Testing

The vehicle being tested is a 1999 Chevy Suburban with no fuel pressure. This truck had a new fuel pump installed and still did not have fuel pressure. In this video I will show you how to troubleshoot this entire fuel pump electrical system, including the fuel pump relay, wiring and computer. Engine Performance Diagnostics chapter 3 page 26 Symptoms - no start with good spark - no fuel pressure - no trouble codes Fix - repair wiring to the fuel (new pump was wired backwards Tests shown - how to test a fuel pump relay in a power distribution box. - power side switched circuit design description and operation. - Fuel pump power and ground testing. - how to manually jump a fuel pump from the fuse box - how to test a fuel pump relay - relay pins (what each one does and how to test them) - how to verify computer control of the fuel pump relay - bias voltage (what is it, how to use it, how it can cause misdiagnosis when using a voltmeter) - wiring diagram review of a fuel pump relay circuit in my classroom (a ScannerDanner premium segment) - how to measure fuel pump current - what sets a fuel pump relay control trouble code Tools used - ATD Tools 5519 Auto Ranging Digital Multimeter - incandescent test light - backprobing pins AES' Electronics Accupuncture Probes Playlist - (Chapters 14, 15,16) Fuel Delivery and Fuel Pressure Testing Related videos - Fuel Pump Electrical Circuits Description and Operation - Fuel Pump Relay Problem - How to test and fix a PGM-FI main relay on a Honda, Acura - How to test an electric fuel pump (1997 4.3L Chevy Blazer CPI) - Fuel pump electrical circuit diagnosis (no fuel pressure testing) GM For more information on this topic, I have written a “field manual” called Engine Performance Diagnostics which is available at 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 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!

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Fuel pump relay testing that can be performed on most makes and models. » Subscribe: » Website: OTHER VIDEOS THAT MAY INTEREST YOU » Fuel System Maintenance: » K&N Fuel Filter Replacement: SOCIAL: » Facebook: » Twitter: Tools Used: Safety Glasses 12v Battery Digital Multi-Meter 10mm wrench Wires with alligator ends Note: This video is being performed by an experienced tech. Any attempt to repair automotive parts and/or systems carries risk of personal injury. Always adhere and follow safe practices when working on vehicles. Such as, use safety glasses, jack stands, no loose clothing, etc. No guarantee or warranty is implied. Use the information in this video at your own risk. If you don't think you can perform the job then be smart and don't. Publication, reproduction or distribution of this film is strictly prohibited. Fuel Pump Relay Testing and Replacement: Carsntoys