How to perform a Starting System Voltage Drop Test

Voltage drop test will help find unwanted resistance within the circuit. Performing a voltage drop test will pinpoint the source of the fault. I also used a thermal imaging gun to prove that the multimeter will not lie if test is done properly.
TIMELINE:
0:00 Intro
0:45 Voltage drop test positive side
4:50 Voltage drop test negative side
20:25 Thermal imaging testing

Пікірлер: 45

  • @carlosdelossantos7212
    @carlosdelossantos72122 ай бұрын

    Señor I don't remember seeing that thermal imaging gun when I was in your Class. Very nice explanation. Being comfortable with the meter and understanding what test you're performing will help pinpoint the problem every time. Good stuff sir.

  • @rolandsmith2141
    @rolandsmith21412 ай бұрын

    My auto electrical skills are not very good videos like this are so appreciated and enjoyable, thanks mate

  • @cbarkwell1000
    @cbarkwell1000Ай бұрын

    EXCELLENT Voltage Drop Testing method...Your only MAJOR Fault is that you didn't tell the Public where both ends of the Green Jumper wire were connecting too to partially Crank the Engine.

  • @davidparker9676
    @davidparker96762 ай бұрын

    Takes me back to Trade Tech days. Very well demonstrated and explained. The FLIR camera really helps speed up diagnostics like this.

  • @transmitterguy478
    @transmitterguy4782 ай бұрын

    Great video! I'm a Certified Electronic Tech and never thought to check my own truck for voltage drop on the starting sequence. Thanks.

  • @MAZMSPBRA
    @MAZMSPBRA2 ай бұрын

    Amazing explanation!!! Straight and clear with the test procedure!

  • @jeffg1149
    @jeffg11492 ай бұрын

    Really should be attached to the post. If there was a poor connection at the battery this way would miss it

  • @chadh3441
    @chadh344115 күн бұрын

    What a very detailed video! Great job and thank you for taking the time to share it! I've watched several videos dealing with voltage drop, but by far, this one is the most detailed and comprehensive yet. Cheers

  • @MRDIAGNOSTECH

    @MRDIAGNOSTECH

    Күн бұрын

    Thank you

  • @nickayivor8432
    @nickayivor84322 ай бұрын

    Welcome back, MR DIAGNOSTECH 👍 SHREWD, MR DIAGNOSTECH From Nick Ayivor from London England UK 🇬🇧 07:39AM Good Morning 🙏 🌄

  • @1231234abcab
    @1231234abcab2 ай бұрын

    Very good explanation 👍🏽 The thermal imaging gun is a nice addition to the diag tools !

  • @8power0
    @8power02 ай бұрын

    VERY GOOD EXAMPLE ,,, THANKS FOR YOUR TIME !!!!!!!!!!!!!!!!!!!!

  • @ShahzadShahzad-eo2ix
    @ShahzadShahzad-eo2ixАй бұрын

    Very good explanation thanks

  • @bwasman8409
    @bwasman84092 ай бұрын

    Very well done presentation! I've watch many that lose me through their's. Keep up the good work!

  • @MukeshSingh-xy7cz
    @MukeshSingh-xy7cz2 ай бұрын

    Thanks for a flawless and finely explained video. Iam a electrical auto mechanic. I haven't come across such a video. Keep it up sir

  • @MRDIAGNOSTECH

    @MRDIAGNOSTECH

    2 ай бұрын

    Thank you very much. I'll keep uploading more videos more frequently.

  • @garylewis3641
    @garylewis3641Ай бұрын

    Very good video, enjoyed it!

  • @Charles_S.
    @Charles_S.2 ай бұрын

    Very well explained 👍

  • @ThunderbirdRocket
    @ThunderbirdRocket2 ай бұрын

    That’s great ! Thanks for sharing this lesson with us !!

  • @stationaryenginesworldwide
    @stationaryenginesworldwide2 ай бұрын

    Great video sir ! Very well explained ..looking forward to more .

  • @bobcote4893
    @bobcote48932 ай бұрын

    Excellent video. Thanks. It would also be helpful to show how you are cranking the engine.

  • @jackburton2680

    @jackburton2680

    10 күн бұрын

    I assumed a second person sitting in the driver's seat

  • @mohammadbenattia9102
    @mohammadbenattia91022 ай бұрын

    Thank you

  • @jackburton2680
    @jackburton268010 күн бұрын

    How do you do the first test if your starter won't crank the engine at all Should a failed attempt aka just turning the keys still energize the circuit suitably for this test?

  • @ritchieschofield1185
    @ritchieschofield11852 ай бұрын

    That's a healthy battery!. Great video

  • @naseembeg5396
    @naseembeg53962 ай бұрын

    Nice video

  • @shakeelsss
    @shakeelsss2 ай бұрын

    Do you give one on one session on how to read wiring diagrams?

  • @trygveseljeflot6245
    @trygveseljeflot62452 ай бұрын

    Forgot to test voltage drop over solenoid contacts ?

  • @rambleon2838
    @rambleon28382 ай бұрын

    What does determine the amount of voltage drop being acceptable?

  • @MRDIAGNOSTECH

    @MRDIAGNOSTECH

    2 ай бұрын

    Positive side: 0.500v Negative side: 0.200V

  • @rambleon2838

    @rambleon2838

    2 ай бұрын

    @@MRDIAGNOSTECH Is this manufacturer specific or in general for 12V systems? Thank you.

  • @MRDIAGNOSTECH

    @MRDIAGNOSTECH

    2 ай бұрын

    @rambleon2838 This are standard specs for electrical circuits.

  • @huupham1025
    @huupham10252 ай бұрын

    Great video! I wonder why you do not test the resistance so you do not have to crank the engine.

  • @MRDIAGNOSTECH

    @MRDIAGNOSTECH

    2 ай бұрын

    That's because it passed the resistance tets. A bad wire could still pass a resistance tets. The best reliable test is to perform a voltage drop test while current flows on any electrical circuit.

  • @joehead1294

    @joehead1294

    2 ай бұрын

    The resistance is too low to measure. E=IxR For example 500 millivolts divided by 150 amps equals 3 milliohms. Or 150 amps times 3 milliohms equals 450 millivolts. But you need two of the three values to calculate. Not sure what the amp draw was in this test. I'm just using a value for the formula. Ohm's law.

  • @joelopez40oz23
    @joelopez40oz232 ай бұрын

    Did this vehicle have any symptoms? I noticed cranking sounds normal.

  • @MRDIAGNOSTECH

    @MRDIAGNOSTECH

    2 ай бұрын

    No symptoms because it had an 800CCA battery, strong enough to crank the engine without issues. This issue could cause a slow crank.

  • @jordysandino6577
    @jordysandino65772 ай бұрын

    Hello sir . Great video . When do you perform that test ? What’s is wrong with the car ? I’m trying to learn . Please forgive my ignorance

  • @MRDIAGNOSTECH

    @MRDIAGNOSTECH

    2 ай бұрын

    This test is performed on a vehicle that has a slow crank wich could be caused by weak battery, bad starter motor, or in this case unwanted resistance on wires and connections.

  • @jordysandino6577

    @jordysandino6577

    2 ай бұрын

    Thank you so much sir . Please keep posting videos cuz we want to learn more about vehicles diagnostics

  • @drazenaudi7864

    @drazenaudi7864

    2 ай бұрын

    Svaka čast na jasnom objasnjenju....pozdrav iz Hrvatske.

  • @jackburton2680

    @jackburton2680

    10 күн бұрын

    Does the test work on an outright no-start situation due to a suspected bad starter?

  • @MRDIAGNOSTECH

    @MRDIAGNOSTECH

    10 күн бұрын

    @jordysandino6577 This test is performed when you have a slow crank condition and you suspect a possible bad starter motor, wiring, or engine. This test primarily check the condition of wires and connections for the starter motor circuit.

  • @rolandos64
    @rolandos642 ай бұрын

    Voltage Drop = Potential Difference (Merely means, If you looked in your pockets, pulled out Your money, then emptied out Your Friends Pocket. What is the difference between Him and You. EX. You have $5.00. He Has $10 dollars. The Difference is $5.00. He Has $5.00 More than You.) under load on the same side!!! Its like testing a wire for continuity. Your DMM should read close to zero. You should see NO to little difference in Voltage/Pressure on one end vs the opposite End. Take Your $5.00 dollars from One Pocket, Place them in the opposite Pocket, youll Still have $5.00

  • @JohnSmith-vt5ry
    @JohnSmith-vt5ry6 күн бұрын

    Can you do voltage drop testing if the starter is not turning over (no crank)? When starting ignition (no crank) the voltage drop from (-) battery to starter housing is 78mv so good. My voltage drop from (+) battery to B-terminal jumps to OL. Its a new good starter. Starter relay is also good. The voltage drop from (+) battery to S lead is also OL when starting (no crank). ???