ITW #10 - Electrical Testing Shortcuts with Vince Fischelli: Part One (Battery Testing)

Motor Age is pleased to once again have Vince Fischelli as a guest on "In The Workshop". In part one, Vince shares tips on battery testing using just a digital multimeter and high amp current clamp.
This is just a sample of the techniques Vince has to share in his 250 page book, "Electrical Troubleshooting Shortcuts". According to Vince, a trained tech can successfully troubleshoot and repair ANY electrical problem with just two tools and he shows you how in this book.
For more info on the book or on the other resources Vince has for you, including hands-on training at his Dallas facility, visit his website at www.veejer.com.
Click this link to subscribe to Motor Age! bit.ly/MA_YT_fr...
Due to factors beyond the control of Motor Age, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. Motor Age magazine (Advanstar Automotive Group) assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. Motor Age 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 Motor Age, 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 Motor Age magazine or its corporate parent, Advanstar.

[@duncanragnar3484]

Man let me tell you! These are some of the best training videos on electrical troubleshooting I've ever come across!! I work on military aircraft, been doing it for 18+ years and most of this also applies to airplane electrical systems too! Love the voltage drop lessons!! Keep it coming! You are doing GOD'S work!! 😇

[@stuzman52]

Hey Pete, this is got to be one of the best videos out there about checking batteries. And all the misconceptions that's been out there for years on how to check batteries. Thanks to you and Vince for taking the time to share.

[@MotorAgeMagazine]

Vince knows his stuff, and was very helpful in making this happen. Support him by visiting his site!

[@arthurbailey2479]

every tow truck driver in the country should watch this video.....even AAA responders. good presentation Vince....

[@vincefischelli7115]

True. Kirchhoff's Law: The sum of voltage drops around a closed circuit equal the source voltage. This means the battery cables each drop 1.0 volt so the shorted battery voltage stays at 10.5x volts with the good jump battery connected.

[@nickayivor8432]

Good Evening Pete Meier and Vince Fischelli Great tutorial thank you 👍 From Nick Ayivor from London England UK 🇬🇧

[@pitchforkpeasant6219]

U guys across the pond having any problems finding car parts too?

[@mike-yp1uk]

Sold. This video was awesome because the content was explained and presented so well. Thanks

[@fivefortyeye540i]

I just want to say thanks for taking out the time and posting these great seminars ..

[@MotorAgeMagazine]

Glad to hear it, Robert. We do what we can to support our teachers. In fact, we have an industry panel discussion planned for September 4 you can watch right here on KZbin! And a great training webinar coming up on August 22 at 8 pm Eastern. You can find out more by connecting with us on Facebook or Google+!

[@turningwrenchesautorepairm5017]

Interesting, i have been using my amp probe to check for "recharge current" for a few years now. Check this out, i recently replaced my oem battery on my 2017 4runner a week or so ago. But before replacing it, i used my amp probe to see the recharge current. I notice that is would drop below 10 amps fairly quickly but It took it took about 5 to 6 mins to drop below 3 amps, This was my first test. A few weeks later, same test. It now took 8 mins to drop below 3 amps. Now about a month later, it took 10 mins to drop below 3 amps. I then used my battery tester and it stated "replaced battery". With a new battery installed, it dropped below 3 amps in less than two minutes.

[@robe5000]

Thank you for providing information like this for free(that goes for all of your videos) keep up the good work

[@MotorAgeMagazine]

According to Vince, yes. For a more complete explanation of why contact him direct via his web site (link is in the video description).

[@videosenutube]

Eye opener,have watched 3 times and I am still digesting all of this info.thank you .

[@fivefortyeye540i]

Wow, very very interesting.. Thanks Pete for taking out the time to put these very informative seminars together it is very very appreciated here.. That Vence cat is very knowledgeable as well as u Pete.. Thanks agin for sharing the knowledge.. Waiting on the can bus seminar

[@euroauto61]

Eric Dibner here spent 2 weekso with u in TX Texas 2 step changed my world !!!!!

[@vincefischelli7115]

The battery OCV is accurate when the battery has been rested for a while. In cold weather the battery will settle down in 15 minutes. In hot weather it may take an hour to calm down. Leave key OFF to allow battery to calm down.

[@MotorAgeMagazine]

Glad you found it informative!

[@Viper81766]

Another amazingly educational video. This will help me in my classes. God bless you guys.

[@MukeshSingh-xy7cz]

Excellent and very informed video. I would love to watch all your videos pertaining this subject.

[@MotorAgeMagazine]

Stand by for parts 2 and 3, covering starting and charging system testing! And thanks for taking the time to comment!

[@fivefortyeye540i]

Thanks. I'm no automotive tecnichan and I have no formal training in the field, but I am fascinated with modern automobile.. Lets face its the automobile is a large part of our life, bread and butter as some would say.. And these automobiles are becoming more and complex by the yr..

[@rogertech6633]

excellent video and explanations, clearly Vince has the knowledge and experience needed! people have learnt much from this guy's videos..great stuff!!

[@pablojr.h.lamsis8003]

I used Vince book in introducing troubleshooting techniques way back 2014 to my students.

[@bleebleblahble8833]

Vince is a legend

[@im7401]

HI I found this video to be very informative and easy to understand Thank you very much Vince

[@euroauto61]

Training is the best tool in and out of any tool box If u are listening to this you are on your wayou You don't know what you don't know !

[@motorman1700]

Great video! I always learn something on your website! Thanks!

[@vincefischelli7115]

OCV is tested with key-off and battery cooled down. See my post above.

[@MotorAgeMagazine]

Correct. OCV stands for "Open Circuit Voltage" and is a measurement of the battery's potential with NO loads applied.

[@pigeonsil240sx]

37:11 wonder if FLIR infra red thermometer would be worth a buy as it only takes a second to use.if the generator heats up from over amperage it will be lit up like xmas tree.not to mention could use it to see high resistance in wires that heat up wires/connectors/devices this could be used to catch things before they even become a issue.

[@MotorAgeMagazine]

It is imperative that you check the NET amount of current. If you are clamped around all the positive or negative cables at the battery you should get a consistent reading.

[@MotorAgeMagazine]

I would test the OCV first. If it's above 12.5 volts, I would continue with a load test. Less than 12.5 volts means it is 20% or more discharged and then I would charge it to see if it was the car's fault or the battery's.

[@James-fs4rn]

👍 thanks for sharing your vast experience!

[@proudofthe3211]

Incredible training! 👍

[@sharanjeetsran6728]

great videos for beginners.

[@gormenfreeman499]

Great tips to avoid buying the customer a new battery. I think many automotive textbooks explain these things like not adding water to the battery if plate is exposed but dont explain how the customer will accuse you of doing something to thier battery.

[@MotorAgeMagazine]

Current if electron flow and is not differentiated by AC or DC voltage. Was there a specific reading you had a question about?

[@vincefischelli7115]

Yes they are and they are placing the battery in hard to get to places on the vehicle. Location doesn't alter the benefits of OCV

[@electronmarkboggess63]

In S.W AZ we go through batteries like water,120 deg here in the summer is very normal..If you get 3 years out of a battery you're very lucky..People that just move here and their battery buys the farm mid way though their second summer here all say the same thing "no way it's the battery it's only a few years old I thought they last about 5 years or so"... well sir welcome to the Sonoran desert lol

[@vincefischelli7115]

I confirm. A shorted cell cause OCV of 10.5x volts. Don't waste your time trying to jump start. The battery is done for. recycle it.

[@jamesdavies7526]

Here in the US Southwest summer time idling in traffic with AC on high kills its share of batteries.

[@authordavidlwallace1499]

Great article since this increased in electron current is a measure of the batteries internal resistance, shouldn't the number of volts measured on the negative side of the circuit be elevated during a voltage drop test? It seems that the increased resistance in the battery would leave less voltage for the load in this case the alternator thanks in advance for your response

[@fivefortyeye540i]

Ocv is conducted when with key off correct??

[@codyshaylyn]

very good video great help to many technicians. A Question for Vince l work on 24Volt systems . The electron current flow for London buses is always around 13 to 18 amps is that ok for 24Volt systems

[@vincefischelli7115]

Go to www.veejer.com/moretraining.html for our training on 24V systems.

[@MotorAgeMagazine]

Thanks! We're trying to keep the pipeline open!

[@vincefischelli7115]

OCV iis done with the key off and the battery has time to cool down from a recent engine run. This may take an hour or more in hot weather, less time in cold weather.

[@fivefortyeye540i]

@Vince Fishelli I'm your first subscriber .. Are u going to start any educational videos here on youtube, or your website? Like your Lectures u hold in Dallas I'm from Houston by the way..

[@CHIBA280CRV]

Wow that was very helpful!!! Question is this test done with everything on the vehicles jut off and just idling? Thanks fellows you guys are great?

[@HikerBiker]

I'm a retired mechanic and I'm very impressed with this video. I've learned a few things I never knew and also some things I was taught wrong. I have a question I hope I can get a truthful answer even though I know this video is over 5 years old. I have a 2018 Transit 250 with a 150A alternator. I'm installing solar for charging 3 100Ah Lithium house batteries and I want to add what is called a battery-2-battery auto charging system. This is designed to monitor when the house batteries are low and then allow the alternator to charge them while driving while also keeping the vehicle going. It is designed to shut off after about 20 minutes and then later turn on again to let the alternator cool down so as to not damage it. It also will separate house and starting batteries so not to draw power from the starting battery. After hearing about how the alternator should drop the amount of current down so soon after starting the engine to protect it I'm wondering if this battery-2-battery system will be ok. Hope you can help

[@cbarkwell1000]

5.17.2019 Long Beach, CA. I would look for Vince Fischellis' Email Address that is on plenty pages of his Website..Place your question there. www.veejer.com

[@vincefischelli7115]

Sound like it is well designed system to protect the alternator from excessive charging. I suggest you check house battery OCV. IF it is 12.6x volts when you park at night you will know the house battery is fully charge. Lower than 12.6x voltage is less than full charge. You need my book www.veejer.com/moretraining.html. Read about it then order. It will answer a lot of your concerns.

[@wave3151]

The battery draw the charging current from the Gen 20amp constantly, that makes the Gen fail due to excessive heat damaging the diodes. Then what about turn the head light and a/c that draws more than 20amp constantly but it doesn't fail the Gen damaging the diodesl i don't see the difference would you help me ? THANKS

[@vincefischelli7115]

Good question; The battery should draw less than 10 amps. This is a constant load on the gen. Keep it as low as possible. If battery draw gets to 20-25 amps that is a constant load in addition to the norm load on the gen that adds to gen output. Too much load heats up the diode bridge. Watch the battery especially if you have a gen failure. It may be the battery that did it. A new gen will fail if the old battery remains in the car.

[@antoniotrujillo547]

very well explanation thank you all

[@vincefischelli7115]

I have workshops scheduled in Dallas starting on the first Monday in December 2013. Stop by my web site and read about the Phase 1, Phase 2 and Phase 3 workshops.

[@txs17]

great video , so your current clamp amps should be about the same with multiple batts say in a heavy truck with 4 batts hooked parallel you would measure off the single ground at the batts, what about a split system each ground should show under 10 amps?

[@qamarhaq8650]

mind blowing

[@phillyflash43]

Good info...however I don't envision many mechanics agreeing to replace a battery they let die for free unless it was under warranty...I think they'd just say it was a coincidence...

[@authordavidlwallace1499]

I have a AMES AC DC clamp meter. when performing the BATTERY recharge electron current test when I place the clamp around the negative cable, should I be taking a DC amps measurement to measure the CURRENT?

[@MotorAgeMagazine]

A battery that low should be charged first. Even if you do get it started, the demand on the car's charging system would be great and could lead to damage to the alternator. The days of letting your car charge your battery are long gone. Hooking up the jumpers in parallel would increase the amperage capability and is, IMHO, not a safe option. May blow the jumped battery!

[@felplayvina]

interesting thank for the video..

[@meblake7359]

I just had a customer that the alternator had a short to ground and the battery drained due to lights being left on to .007v. We recharged the battery and tested it with a snap on diagnostic tester and it passed as good. After replacing the alternator, everything works fine and the customer has not come back for weeks. How can your SOC be an absolute?

[@view4me24]

Great Vids what is the reading of current in ac or dc

[@johnkimmel2612]

Is Vince basically saying it is not a good idea to use , say the Sun Vat40, as damage may occur to alternator/generator while load testing battery while connected to circuit of vehicle ?

[@MotorAgeMagazine]

Yes, exactly right. Loading the charging system to check maximum alternator output could cause more harm than good. Now, there are too many alternatives to testing the system.

[@vincefischelli7115]

It's not good to put a carbon pile tester on battery with engine running. Many do it but don;t relalize how wrong it is. Getr my book www.veejer.com/shortcuts.html

[@victoraberdeen2634]

I have encountered a situation where I obtained an amp reading of 75amps during idle on a vehicle.The maximum rating of generator was 140amps.I still blame "MURPHY"

[@euroauto61]

It's all about the amp Amps =HEAT

[@Turbotomass]

These OCV readings are after you've attempted to charge the battery correct? Lets say you get a tow in or a car's been sitting, etc. I assume you would try to charge the battery before you condemn a battery with these readings. If a car made it to the shop and was previously running or simply sat over night and there's no draw then the numbers would be accurate for diagnostics?

[@vincefischelli7115]

OCV is only valid test of battery state of charge when battery has been resting for at least one hour. After charging or engine run wait at least 1 hour for battery to calm down.

[@felplayvina]

Hi Pete, if the battery read 11.89 V the battery is just low and still can use a jumper cable? I have seen people use a jumper cables and jumper box at the same time because the car won't crank with one of this WHAT DO YOU THINK ABOUT THAT?

[@jeffsweensy341]

excellent ! I have one question . Is the amp probe measuring only battery current draw or total current out put of alternator?

[@vincefischelli7115]

Depends where you place the clamp. Connect clamp around all cables and wires connected to the negative side of the battery to read battery draw during engine run. You should see less than 10 amps.

[@vickenkaragozian2041]

Hi Vince. i have tested current right behind the alternator with loads on, for example 80 amps. But the alternator wire goes to a fuse box, then from the fuse box to the battery positive cable. The amperage from the alternator to the fuse box is 80 amps but from the fuse box to the battery is much less like around 40 amps. Can you explain to me why ? I could never figure it out. i have done voltage drop on both negative & positive side but still 40 amps. Not sure why. Can you let me know ? Thanks.

[@everardocamacho5063]

hi Mr Vince, great all u videos, where do I get the current clamp and what brand and model, I would like to buy me one , not to expensive, thank you

[@cbarkwell1000]

5.17.2019 Long Beach, CA. www.aeswave.com Fresno, CA. DC Amp Clamps : You either type in Multimeters or go to the Teachers Section --- Click on Vince Fischelli with Pete Meier..Look for Amps Clamps, the Clamps with Banana Plug Ends.

[@vincefischelli7115]

Google CA600 current clamp. Then order one with the best price.

[@tlazintla1]

thanks for the video i wish i can take one of your training classe iam in clearwater florida,

[@shacoclone3299]

Florida! *Highfive!*

[@bmw-e30]

Do you know why batteries fitted to new vehicles last 2 to 3 times longer than replacement batteries bought in Auto factors. OEM batteries can last ten years or more while Motor factor batteries even reputable brands struggle to last 3 to 4 years or as soon as the warranty expires.

[@vincefischelli7115]

Sound like you haven't found a reliable source for batteries. Keep trying battery companies until you find one that lasts. Make sure any battery supplier stands behind thier warranty.

[@view4me24]

Thank you

[@vin605]

Excellent ! I owe you 50 pushup's

[@view4me24]

My meter has a clamp built in to it but it only reads ACV/DCV/ACA will that work to test the alt. amps in the test in part 1

[@vincefischelli7115]

Your clamp must read DC amps. That is what flows throughout the electrical system.

[@hddm3]

25.00 awsome

[@vincefischelli7115]

keyy off long enough for the battery to cool down from the last RUN cycle.

[@victoraberdeen2634]

A digital current clamp makes these measurements way more easier.

[@mohawkmike142]

Jason K asked this below with no answer. How come it's OK to run 28amps thru the electrical system running devices constantly but not 28 thru the batt as recharge current? I don't see the difference either.

[@MotorAgeMagazine]

It's the NET current that is the issue. If the system draw is 50 amps and the charging system feeds 50 amps with a little left over for the battery (say, 5 amps to keep it simple), then that is a NET 5 amps. When the battery is sulfated or has a damaged, but not quite dead, cell it takes more to keep it happy and the net increases. This puts an undesigned overload on the system, same as installing too many accessories on a car, and overheats the alternator leading to premature failure.

[@vincefischelli7115]

Because what the battery draws adds to the 28 amps to run the vehicle. If battery draws 30 amps add that to 28 amps and watch the gen diodes start to get hot and eventually fail.

[@shaneparsons9303]

Where can you buy these amp clamps like the one you use ?

[@MotorAgeMagazine]

Try AES...www.aeswave.com/

[@vincefischelli7115]

Google CA600 current clamp.

[@vincefischelli7115]

You must be able to read DC amps

[@pitchforkpeasant6219]

Doing wrong means push ups. Hire the skinniest weakest graduate from his class then. 🤣. Great info. Thanks being words for these educational videos 👍👍

[@euroauto61]

This is your original first thing first Updated

[@vincefischelli7115]

DC Amps

[@vincefischelli7115]

don't do anything to the battery. It must be calmed down (chemically) to get an accurate OCV. If it is towed in the battery should be calm to check OCV before you do anything else. If the battery is recharged allow about 2 hours for the battery to cool down before checking OCV.

[@thnkbg]

Can I get a job or make money with these skills or do I need to go to school?

[@MotorAgeMagazine]

There are a number of fields where a knowledge of electrical circuits is vital. Automotive is just one. With some foundational knowledge, you may get your foot in the door and some companies will train you themselves.

[@vincefischelli7115]

DC amps

[@charlesgould8436]

This is a few hours that will change you.

[@vincefischelli7115]

everything is shut off. Key-OFF for a while to let the battery to calm down.

[@jh90713]

He talks too much, I dont need to know somthing as stupid as where to buy distilled water. Get to the point and quit telling stories. You could cut 75% of this and not leave out any useful information.

[@truth4reel]

some people are ungrateful $#@itches. You get this free knowledge and still find a reason to disrespect?

[@cbarkwell1000]

5.17.2019 Long Beach, CA. ( Los Angeles County ) Jh90 is probably one of those guys who has never heard of a Battery Leakage Test also, just by listening to his absolutely silly response to Vince Fischellis message. When your DVM Black Lead is attached to your Negative Battery Post & you Drag the Red Lead all across the Battery Top : .5 Volts, 1 Volt, even 4 Volts & more I've seen on Customers vehicles. The Battery Voltage belongs inside the Battery , not on Top of it. Battery Voltage read on Top of the Battery Case will DECREASE the LIFE of any Battery.

[@vincefischelli7115]

I think I made several good points and the stories lend support to the test procedures getting the job done. They help techs understand. Sorry you are having a bad day.

[@edwardlara1011]

You're an ingrate jerk. I wouldn't want to work with an asshole like you ever.