In this video I show you my process I use to make the call on an alternator that I suspect is faulty. How do I know 100% for sure? Simple, TEST DON'T Guess! -Enjoy!
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Adjustable Insulation Piercing Test Clip with B-plug Inputs (AES # PE-10) : https://www.aeswave.com/cart.php?m=affiliate_go&affiliateID=2525b91fc8e906e8215984074c9d9e8f&go=https://www.aeswave.com/Adjustable-Insulation-Piercing-Test-Clip-with-B-plug-Inputs-p8507.html
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49 thoughts on “Vehicle is not charging: how do we know it is the alternator?”
  1. Avataaar/Circle Created with python_avatars Richard 1 says:

    Great video to learn about the Alternator/Charging Circuit. Thumbs Up

  2. Avataaar/Circle Created with python_avatars Richard 1 says:

    Thank you SMA

  3. Avataaar/Circle Created with python_avatars Travis says:

    "as Scotty always says" ? r u talkin about Scotty Kilmer??? that dudes wild, i think id like his stuff but even with good coke, i cant snort enough at once to keep up with him

  4. Avataaar/Circle Created with python_avatars John Smith says:

    What did you do here, again????

  5. Avataaar/Circle Created with python_avatars Tyson Leyba says:

    hey! sweet vid, what is the little tiny scope you're using? do you like that one better than the vantage pro scope???

  6. Avataaar/Circle Created with python_avatars James Lacy Kamuf says:

    Excellent work as usual!

  7. Avataaar/Circle Created with python_avatars boil shifter says:

    Out of the first 30 seconds of video I'm beating battery not alternator

  8. Avataaar/Circle Created with python_avatars wolf north says:

    you stated that the wire connecting the alternator and the battery is doing the voltage drop, why did you change the alternator? should you change the wire first?

  9. Avataaar/Circle Created with python_avatars José Spn says:

    Could you tell me Where can I get the Uscope ?

  10. Avataaar/Circle Created with python_avatars Richard Merold says:

    great video

  11. Avataaar/Circle Created with python_avatars richard newton says:

    my ram van 1500 3.9lt NEEDS 14.3 volts or it trips computer tested my battery perfect 12.5…turn motor 13.9…ok alt good but for what ever reason this truck needs 14+ to work computer. wth. ??????

  12. Avataaar/Circle Created with python_avatars Mk L says:

    I actually have that exact engine I was looking forward to the replacement steps. Judging by your comments, I'll have to leave myself ample time to replace when that time comes. 2007 185k with the OG alternator.

  13. Avataaar/Circle Created with python_avatars Kerry McQuistian says:

    What is the little scope you were useing

  14. Avataaar/Circle Created with python_avatars Bernarda Flores says:

    Can you help w/ a link for the small scope??
    Great channel.

  15. Avataaar/Circle Created with python_avatars Eric Downer says:

    I can almost smell the markers. Thank Eric Ohhhh.

  16. Avataaar/Circle Created with python_avatars N.B says:

    The front mounted fan drawing looks like a dragonfly hahahahaha

  17. Avataaar/Circle Created with python_avatars Pat Meek says:

    If the uscope test is failing is that a bad ecu?

  18. Avataaar/Circle Created with python_avatars Alexander Cahoulan says:

    I love Eric O. Plain and simple.

  19. Avataaar/Circle Created with python_avatars trangia94534 says:

    Thank you for taking the time to teach us.

  20. Avataaar/Circle Created with python_avatars Ghostgunner27 says:

    What’s Roebuck 🙄😭

  21. Avataaar/Circle Created with python_avatars Eric G says:

    I don't get it, can't u just test voltage at battery and then voltage at alternator and if they are the same then why do a voltage drop test?

  22. Avataaar/Circle Created with python_avatars Alena Anberg says:

    Informative, thank you! I am a teacher and can say great job teaching!

  23. Avataaar/Circle Created with python_avatars Jeff Becker says:

    I like the way every video is like a shop class. Very well explained

  24. Avataaar/Circle Created with python_avatars Jeff Becker says:

    When cars begin doing many abnormal things, and you get a major light show going on with the dashboard, pretty good indication that you have a failing alternator.

  25. Avataaar/Circle Created with python_avatars Joe Mikos says:

    Another great vid!! TY Question…If there were no pwm from the computer and you strongly believe the computer is bad how do you test the alternator on the car (I have this situation currently and the alternator is a pain to R&R) I would rather tell the client that the alternator and ECM are bad up front if that's the case. BTW I have confirmed a bad ECM starter circuit also.
    Thank you, Joe

  26. Avataaar/Circle Created with python_avatars 505 fast life says:

    Is there any way to check the computer wire with just a multimeter? Also these videos have helped this want to be mechanic learn a ton about diagnostics more than school.

  27. Avataaar/Circle Created with python_avatars MrVeer58 says:

    Many thanks.

  28. Avataaar/Circle Created with python_avatars Erich N says:

    How about waterpump in2010 flex 3.5 non turbo.

  29. Avataaar/Circle Created with python_avatars Mbe says:

    Great teaching

  30. Avataaar/Circle Created with python_avatars John Parsons says:

    Awesome video I’m glad I watched it before I spend 2K on my dual alternators on my 6.0 .I want to make sure it’s the alternators !

  31. Avataaar/Circle Created with python_avatars William White says:

    Thank you very much for this presentation!! Recently my wife's Infiniti EX37 had a brake light and battery light on when she got home from work. I checked the voltage at the battery and confirmed the alternator was not charging. I made an appt. with the dealer for the next morning. The next morning I put my "smart" charger on it set on 30 amps. I started the engine while it was charging and checked the brake fluid low switch and then shut off the engine. After leaving the charger connected a while longer I left driving it to the dealer and the brake light and battery light were off! After getting to the dealer they put a volt meter on the battery and confirmed it was indeed charging. So, I went back home and it continues to work fine. I can only assume the 30 amp charge woke up the car's computer????? Computer brain fart???

  32. Avataaar/Circle Created with python_avatars Av8tore71 says:

    So how do you go from Battery to alt if BTRY is under the rear passenger seat of a 2016 Chevy Traverse? I noticed my volt gave is higher than 14volts on the dash but putting a volt meter my Traverse is charging at 14.6 to 15.0 volts

  33. Avataaar/Circle Created with python_avatars CanDo says:

    That's good testing information for my Honda and Nissan as well. Thanks buddy!

  34. Avataaar/Circle Created with python_avatars george bonney90 says:

    Thank you mr O 👍

  35. Avataaar/Circle Created with python_avatars joe schmoe says:

    Thumbs up for the big SK with a chainsaw

  36. Avataaar/Circle Created with python_avatars Peter Knuerr says:

    Very well covered Not just parts swapping, a very thoughtful consideration of what charges the battery under load conditions, as in rear defroster blower motor on high and headlights all needed for typical winter driving! Stay healthy this winter!

  37. Avataaar/Circle Created with python_avatars John Johannemann says:

    Great job as always!

  38. Avataaar/Circle Created with python_avatars Ian says:

    Eric O. is what separates the men from the boys

  39. Avataaar/Circle Created with python_avatars Richard England says:

    Thanks for the detailed explanation.

  40. Avataaar/Circle Created with python_avatars 1967250s says:

    Au contraire, Mon AMI, I have learned a lot from this video, and I am an aircraft electronics technician, and many of these tests are applicable to most vehicles. Always a pleasure.

  41. Avataaar/Circle Created with python_avatars Brian Aguilera says:

    Thanks

  42. Avataaar/Circle Created with python_avatars Byron Lippe says:

    Alien abduction Radio quit working and other electrical issues. Was she also missing time. (Sorry if I’m a bit late on this comment. I was “away”)

  43. Avataaar/Circle Created with python_avatars Viking 2121 says:

    Good explanation! I had a case with my grandfathers Honda Odyssey, the battery would randomly die, was getting to the point where it needed jumped every day, then it suddenly went away and it occasional, every test it was tested good same with the battery, well he got a new Alternator I put it on, what a job it was… And all seemed fine and it started to do it again, out of the blue, Tested it everything was fine, change the battery anyway, still occasionally did it. I tore the entire front end of that van apart and I found that inside of the sleeve for the hot wire that goes to the alternator was not crimped down from factory enough, this probably had been going for 8 months lol, So glad its fixed, tired of jumping it, and tired of seeing it lol.

  44. Avataaar/Circle Created with python_avatars Wings an things says:

    You need different colour sharpies. LOL.