My auto electrical skills are not very good videos like this are so appreciated and enjoyable, thanks mate
@jessejameson15418 күн бұрын
Brilliant presentation.....one of the best tutorials on KZbin regarding voltage drop on starting circuit.....and I've seen dozens at this stage
@carlosdelossantos72124 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.
@bwasman84094 ай бұрын
Very well done presentation! I've watch many that lose me through their's. Keep up the good work!
@transmitterguy4784 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.
@davidparker96764 ай бұрын
Takes me back to Trade Tech days. Very well demonstrated and explained. The FLIR camera really helps speed up diagnostics like this.
@chadh34412 ай 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
@MRDIAGNOSTECH2 ай бұрын
Thank you
@MukeshSingh-xy7cz4 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
@MRDIAGNOSTECH4 ай бұрын
Thank you very much. I'll keep uploading more videos more frequently.
@itsmisterchris2 ай бұрын
Man your video explains so well to a person who didnt know such test even existed , im excited to learn more n fix problems on vehicles ,
@1231234abcab4 ай бұрын
Very good explanation 👍🏽 The thermal imaging gun is a nice addition to the diag tools !
@MAZMSPBRA4 ай бұрын
Amazing explanation!!! Straight and clear with the test procedure!
@jeffg11494 ай бұрын
Really should be attached to the post. If there was a poor connection at the battery this way would miss it
@cqmacht45133 күн бұрын
Great video thanks for sharing your knowledge with us, this is the best one I have seen on voltage drop.
@bobcote48934 ай бұрын
Excellent video. Thanks. It would also be helpful to show how you are cranking the engine.
@jackburton26802 ай бұрын
I assumed a second person sitting in the driver's seat
@bernardocisneros4402Ай бұрын
One end of the green jumper was connected to battery+ and he was touching terminal 87 of the starter relay with the other end of the green jumper. Don't do this unless you know what you're doing because when you jump terminal 30 and 87 on the starter relay, you shouldn't turn the key to the "ON" position, because the engine will start when the starter cranks, unless you disable the fuel pump or fuel injectors and ignition. If you only disable the ignition, the fuel pump and fuel injectors will continue to work and dump fuel into the cylinders thereby flooding the engine.
@8power04 ай бұрын
VERY GOOD EXAMPLE ,,, THANKS FOR YOUR TIME !!!!!!!!!!!!!!!!!!!!
@ThunderbirdRocket4 ай бұрын
That’s great ! Thanks for sharing this lesson with us !!
@tonyt831413 күн бұрын
Great video!!! where do you get those large alligator clips for the test leads??
@danielpittman88924 күн бұрын
Orale! Exactly what I needed to learn.
@stationaryenginesworldwide4 ай бұрын
Great video sir ! Very well explained ..looking forward to more .
@automaster20918 күн бұрын
The only thing I would recommend is placing the negative lead on the bottom, or motor, terminal include the copper disc resistance in the solenoid.
@Charles_S.4 ай бұрын
Very well explained 👍
@cbarkwell10003 ай 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.
@CrazycuzxyzАй бұрын
U read my mind bruh same question
@bernardocisneros4402Ай бұрын
One end of the green jumper was connected to battery+ and he was touching terminal 87 of the starter relay base with the other end of the green jumper.
@jessejameson15418 күн бұрын
This would be a completely different video , and require a bit more expertise than ordinary diy. He would assume you could get someone to crank the engine. The process he uses should only be used by professionals , as it required bypassing the starter relay, as well as removing the fuel pump fuse. All cars are different as regards this , and any mistake could destroy the cars ecu ....so I'm not surprised he didn't show his process on this.
@nickayivor84324 ай бұрын
Welcome back, MR DIAGNOSTECH 👍 SHREWD, MR DIAGNOSTECH From Nick Ayivor from London England UK 🇬🇧 07:39AM Good Morning 🙏 🌄
@ritchieschofield11854 ай бұрын
That's a healthy battery!. Great video
@plowe675121 күн бұрын
You should do a video on how to do a starting system voltage drop test on a car with the battery in the trunk (or in the passenger compartment).
@ShahzadShahzad-eo2ix3 ай бұрын
Very good explanation thanks
@garylewis36413 ай бұрын
Very good video, enjoyed it!
@mohammadbenattia91024 ай бұрын
Thank you
@naseembeg53964 ай бұрын
Nice video
@ChristopherCarovillano25 күн бұрын
What about battery voltage too low? I cannot pinpoint the source of the fault.
@anthonyheak3479Ай бұрын
MR. DIAGNOSTECH, how did you cranked the engine from the fuse box? Nevermind, I think you had the key to the on position and jumped the starter relay terminal 30 and 87.
@MRDIAGNOSTECHАй бұрын
@@anthonyheak3479 by supplying voltage to the starter relay connector to terminal 87.
@anthonyheak3479Ай бұрын
@@MRDIAGNOSTECH Thanks for replying, you did a great explaining step by step!
@bernardocisneros4402Ай бұрын
When you jump terminal 30 and 87 on the starter relay, you shouldn't turn the key to the "ON" position, because the engine will start when the starter cranks, unless you disable the fuel pump or fuel injectors and ignition. If you only disable the ignition, the fuel pump and fuel injectors will continue to work and dump fuel into the cylinders thereby flooding the engine.
@jackburton26802 ай 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?
@bernardocisneros4402Ай бұрын
Yes, you can and should do this voltage drop test when your starter fails to crank when turning key to the "Start" position. Yes, a failed attempt will energize the circuit so you can do this test.
@steelcamel5626Ай бұрын
are you located in a corrosive area???salwater?
@shakeelsss4 ай бұрын
Do you give one on one session on how to read wiring diagrams?
@jordysandino65774 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
@MRDIAGNOSTECH4 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.
@jordysandino65774 ай бұрын
Thank you so much sir . Please keep posting videos cuz we want to learn more about vehicles diagnostics
@drazenaudi78644 ай бұрын
Svaka čast na jasnom objasnjenju....pozdrav iz Hrvatske.
@jackburton26802 ай бұрын
Does the test work on an outright no-start situation due to a suspected bad starter?
@MRDIAGNOSTECH2 ай 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.
@huupham10254 ай бұрын
Great video! I wonder why you do not test the resistance so you do not have to crank the engine.
@MRDIAGNOSTECH4 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.
@joehead12944 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.
@bernardocisneros4402Ай бұрын
Voltage drop test are superior and more reliable than continuity tests.
@bernardo12196814 сағат бұрын
@@joehead1294 No one cares about the actual ohm value of the resistance. You just want to make sure you don't have high resistance. If you get zero ohms or a few ohms for resistance, that's good enough. We're not trying to solve physics or engineering problems here.
@joelopez40oz234 ай бұрын
Did this vehicle have any symptoms? I noticed cranking sounds normal.
@MRDIAGNOSTECH4 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.
You are confusing , the readings on the multimeter are 0.5 milivolts or volts ?
@bernardocisneros4402Ай бұрын
The reading is 0.5 Volts which is equal to 500 mV
@CesarCano-e7xАй бұрын
@@bernardocisneros4402 thanks for the correction .
@HighGrade_FireBlade20 күн бұрын
You are 100% right. He kept saying the wrong thing. You aren’t misunderstanding anything, he just doesn’t understand what he’s saying. He’s saying “zero point five millivolts” which would be .0005 volts. He should be saying “zero point five volts” not millivolts.
@rambleon28384 ай бұрын
What does determine the amount of voltage drop being acceptable?
@MRDIAGNOSTECH4 ай бұрын
Positive side: 0.500v Negative side: 0.200V
@rambleon28384 ай бұрын
@@MRDIAGNOSTECH Is this manufacturer specific or in general for 12V systems? Thank you.
@MRDIAGNOSTECH4 ай бұрын
@rambleon2838 This are standard specs for electrical circuits.
@sct91123 күн бұрын
@@MRDIAGNOSTECH can the voltage drop tests be done with the car in a started running state? instead of cranking each time?
@trygveseljeflot62454 ай бұрын
Forgot to test voltage drop over solenoid contacts ?
@GL0697Ай бұрын
There was no need to, the TOTAL VOLTAGE DROP on the positive side was within specifications. If it wasn't then yes you are correct that would have to be one of the test points that should be checked.
@bernardocisneros4402Ай бұрын
@@GL0697 No, he did not include both solenoid contacts when he performed voltage drop test on positive side. If he wanted to inlcude them, he would have to go from battery+ to the M terminal on the solenoid not the B terminal.
@GL0697Ай бұрын
@@bernardocisneros4402 Please re-read what I wrote. There is no need to check those terminals separately, when the total is good.
@bernardocisneros4402Ай бұрын
@@GL0697 I read what you wrote and there is a need to check the terminals. I've done this many times and if there isn't good contact between B terminal and M terminal inside of solenoid, you will not catch it if you only connect voltmeter leads from battery positive to B terminal on starter solenoid.
@HighGrade_FireBlade20 күн бұрын
You kept saying zero point five millivolts. That would be .0005 volts. The correct way to say it would be zero point five volts, or five hundred millivolts.
@MRDIAGNOSTECH20 күн бұрын
@HighGrade_FireBlade O.500V = five hundred millivolts. 0.050= fifty millivolts. 0.005= five millivolts.
@HighGrade_FireBlade20 күн бұрын
@@MRDIAGNOSTECH but you weren’t saying .500 volts. You were saying 0.5 millivolts. You had the decimal in the right place but you should have said volts. You are looking for a voltage drop of less than .5 volts or 500 millivolts. Idk where you got 0.5 millivolts from.
@rolandos644 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-vt5ry2 ай 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). ???
@twosm0kerАй бұрын
for a no crank you should confirm battery voltage at b term and confirm 12 v at the s term when trying to start.
@bernardocisneros4402Ай бұрын
When your starter is not turning over, is exactly when you need to do voltage drop (VD) testing. If your readings from battery+ to B terminal and battery+ to S terminal jump to OL when you try to crank it by turning the key to the start position, then you either have a bad battery, a loose/bad/corroded connection at battery+, or very high resistance on cable going from battery+ to B terminal on starter solenoid and very high resistance on cable feeding power to fuse/relay box. The high resistance in these cables is usually caused by excessive corrosion but it can also be caused by physical damage. These are the only things it could be. Please share what it was when you fix it. It might help someone else on here.
@JohnSmith-vt5ryАй бұрын
Yes that is what it ended up being. Corroded bad splice that was on the power cable from years back. Took off the wrapping and there it was..
@bernardocisneros4402Ай бұрын
@@JohnSmith-vt5ry Good to hear you found it. Thanks for posting. It helps others in the future.