How to Test an Alternator ( Testing the Voltage Regulator, Diode rectifier and Stator)

[@JunkyDIYguy]

Guys, check out my latest video kzbin.info/www/bejne/i3iYZauqapuokNE

[@tattedone6753]

I have a question about my vehicle do you have a email I can message you at?

[@djeletropopstarify]

I have kind of dirty but perfectly working alternator, but it's kind of plug up with all kind of junk is there proper way to clean the alternator inside component's? and what it's proper way to do it

[@azizmakka7126]

Very helful vidios

[@azizmakka7126]

Sar. plese show me how to chek ulternet motor (capacitor) rely

[@waziraliwazirali6095]

Hi

[@davidbarlow269]

I am an electrical engineer of some 40 years experience. Your presentation is excellent. Your English is very good. Your video skills are very good. I like the use of gloves , I like your camera skills. Top marks...

[@post3097]

and not to mention the editing👌ur comment is so nice :)

[@StianS-g2e]

Gloves are gay

[@BlackwaterDSM]

Hands down, one of the most informational and concise videos I’ve ever watched. The only way he could tell you more about an alternator is to show you how they wrap the copper up into a spool. Came here due to an overcharging alternator (first one OVERcharging in my 38 years of being a driveway mechanic) and was able to diagnose it thanks to this video. Thank you for such an awesome video!

[@lukula2934]

Could not agree more. It goes to show how many YT "experts" only know enough to be dangerous.....

[@BlackwaterDSM]

@@lukula2934 Right?! They help you out, alright…. Help you right i to the back of an Ambulance (or Hearse). 😬😬😬

[@joeblow1711]

I agree!

[@gradyrm237]

100% the best alternator video on the internet. This cat showed me how to test everything in the circuit. Testing the pins on the connectors was a massive help. I needed to know if the PCU was sending the signal to the alternator first of all. Taking the alternator apart is out of my wheel house. I just needed to pinpoint my defective part. This homie crushed it.

[@konquer247]

It's people like that makes KZbin a great source of information. Thank you for your efforts.

[@arunadevi4734]

You are Knowledge Hub. Great....

[@lucianoferreira613]

My car stopped while driving. Thanks to two of your videos I diagnosed a bad connection between the positive terminal of the alternator and the battery ,gosh, I'm even speaking like a pro :) , I would like to give you a thumbs up for every euro you saved me. Thanks bro!

[@d.d4184]

I am a technician,and this video very good with correct information. Not sure why anyone would give you a thumbs down.

[@cowboyred295]

Idc if this was made 7 years ago you are an excellent teacher/instructor ❤️

[@yyxx5088]

your patience, dedication and keenness to detail is much appreciated

[@jeremyyang7234]

This is the most detailed instruction for testing alternator I have ever seen.Thanks a lot.

[@bobczz3919]

This is the BEST video I have seen on the charging system. I never buy a new alternator or starter. I always rebuild them for a few bucks. I will not pay 300 or more for a new alternator or starter. Thank you for such an informative video.

[@TR4zest]

I found myself pausing frequently to try to absorb all your excellent information. Wow. Thank you.

[@matthewdurkovich9714]

I am chasing a parasitic draw on my sons 2006 F150. All fuses/relays are good. It appears it MAY be the alternator, but it looks newer, so I think there's an underlying issue and the alternator keeps getting replaced - and the amp draw still exists. The truck is new to us, but he's trying to sell it and can't do that until the amp draw is corrected. So I've been scraping the bottom of the internet for good alternator videos. This is a phenomenal video. I dare say the best one I've seen. Editing is SUPER helpful, especially when you have picture in picture views. I will re-watch this a dozen times and likely have what I need. I can clearly see why it has 4.6M views. Thank you sincerely!

[@elebeu]

I especially appreciated the testing of the cables and ground for voltage drops. These are often overlooked and and multiple, small, voltage drops can add up to trouble.

[@tonyjenkins7156]

Helped me a lot. Connector corrosion problem. Day of work, saved $200. Thank you.

[@a.bax.5992]

I've watched quite a few DIY videos on KZbin and this is by far one of the most detailed and clear.

[@danmaryam8201]

Very educative

[@azmyin]

Sir, this was beyond GREAT! I followed the steps for checking a faulty alternator and found out that my friend's vehicle's alternator died due to running a 5+ year old battery

[@CarAudioInc]

the effort you put into these videos is phenomenal

[@JunkyDIYguy]

thanks buddy

[@AlimKhan-xq7mc]

Air Field lighting system how to use CCR and MCR and check the transformer

[@FranklinHicks-qs4gs]

Increase your vocabanizzle

[@randyinchesapeake8129]

Now THIS; in my humble opinion, is what the internet was created for. To SHARE INFORMATION! (at one time called "the information superhighway") And this man did a damned good job of it!

[@Roudter]

I like how you measure for voltage differences between the terminals and their endpoints - eliminating connection problems. It's a good method for any older vehicle.

[@humanresource9659]

I know I'm basically repeating what another reviewer said but it popped in my head before I read their comment so I'm about to say it now: This is the most comprehensive review of an alternator I have ever seen Keep'em coming

[@minaflores1018]

I just wanted to thank you for being so specific when explaining how to test and what to expect to see. This is the best video online. Trust me when I say I have watched and or read almost everything available online and not one comes close to being a thorough as you. I have been trying to figure out why my new alternator and new battery in my 2002 c320 still is not charging I found myself in an under information sh&% show. Thanks to you I have all the information needed, so that I can go back out to my car and have a good chance in figuring out my issue. Thank you so very much for your help. Keep up the amazing work. its really appreciated. :)

[@JunkyDIYguy]

thanks mina

[@Decimusblack88]

Did you figure it out?

[@peterd.1165]

Your video is very professional and brilliant - I have a 1996 Volvo 940 fitted with a Denso alternator (100/14) - some time ago it started to make a whining noise. So far, I have replaced the bearings and drive belt - The Alternator is in outwardly good condition but the Whine persists. With the engine running, the whine is stopped when the large battery lead is disconnected from the alternator and resumes when the lead is reconnected. It has been suggested to me that the noise may be coming from the rectifier.

[@nil4309]

Definitely the best video on this! Not only explains what to test, but why - and exactly what each component should be doing. Thank you

[@arifmohiuddin9933]

Amazing camera handling, camera quality, video editing, detailed but very precise and quick leaving no point left. To me it's not just DIY but deep research based contents. Exceptionally well done.

[@andysmith7758]

This is a GREAT tutorial! Technically right on, and thorough demonstartions and explanations! You know your stuff, DIY Junky! Thank you so very much!

[@rdyam]

I've got a wide range of interests that I look up tutorials for and there's a very good chance this is the best I've ever seen - thanks!

[@mudassirnaseem6111]

very nicely explained. i would like to add couple of things plz excuse me. while checking the rotor & stators also check their ground resistance. i.e their should be very high resistance between slip rings & its shaft, also between stator & alternator's body. thanks

[@Etheo1ify]

The most detailed video on how to test, diagnose and repair an alternator. Thank you!

[@autopilotone4]

Thank you so much for an informative video. I have a parasitic drain and have pulled every single fuse in the car and it does not make any difference. Put a voltmeter switched to AC across the battery and wow, 29 Volts AC! That looks like a bad diode in the alternator!

[@seanys]

This is the only alternator video I’ve found on YT that covered what I actually needed know. Well done and thank you.

[@RS-yj3gn]

This must be the best tutorial i have seen. Easy to follow and well illustrated. Thanks so much!

[@cheonglin1019]

The is the best and most comprehensive video on alternator testings and diagnosis

[@habsom1406]

Superbly explained video. Clearly a very knowledgeable individual who knows his alternators and automotive electrics. Thank you for making, editing and uploading this reference quality tutorial. 😎👍

[@verylittlehouseonwheels5892]

You did a good job man I'm just a guy that worked under a quad Master certified mechanic that love to teach. You hit on all of it. He made me a mechanic where most people want to be a mechanic. I never use a book only for torque specs now that I'm not a active mechanic tend to watch a KZbin page for surprises that book won't tell you the surprise once in the job

[@johnnymorris55]

An exceptional demonstration of automotive mechanical, electrical knowledge. Shared so others can learn and gain from your experience and hard work. I take my hat off to you friend. Well done.

[@anthonyheak3479]

Excellent tutorial, thank you! To remove the decoupler pulley, you forgot to mention that we need to block the rotor from rotating.

[@jimnorrison8481]

I just became an expert on automotive batteries and alternators.

[@24pionu]

MzMa

[@anhLe-hn3ig]

Best video to explain how to debug and repair a '09 - '13 Toyota Corolla alternator I have seen. Awesome dude! Thx Your English is excellent. I just replaced my '11 Corolla alternator, so I can attest the alternator used in this video. I wish I have the confidence to repair / rebuilt my own alternator rather than paying Autozone $305 after tax for a refurbished one in Jun '24.

[@robertculver3014]

Excellent. Does not waste time on simple actions. Goes deeper than many such sites.

[@robbym.2154]

Dude!!! You are my guru!!! Smart, concise and such a welcome breath of fresh air instead of the miles and miles of useless b.s. you find all over the net. Thanks man!!! U rock.

[@wrengouws3944]

Brilliantly laid out step by step explanations and visual points! My friend I have legitimately gone through hundreds of videos here on KZbin and yours was by far thee best in this category! I'm going to be in here like swimwear and dive right into your other videos! Very well done mate!! And thank you for creating this channel!! 👌

[@JunkyDIYguy]

Thank you very much

[@JaceD4V1S88]

my alternator is on a 94 previa, recently the headlights, dash and dome light intermittently dim and brighten slowly like im flashing someone with my headlights but its very subtle but noticeable. been watching videos on how to replace some of this stuff myself as i cant buy a whole new alternator right now. very informative vid, thank you!

[@HamzahVerster]

The most informative video I've ever seen on KZbin 👌🏼 Well done mate. Please continue making videos like this. I wish you all the best and good luck 🙏🏼

[@ocean115]

Wow, one of the best videos on the internet regarding auto electric repairs & testing. So much precise information, very well videoed & easy to understand!

[@BlueMoonDIYs]

this is by far the best video on car alternator basics., on how it works and how/what to test👍

[@Mr.Tiger.2013]

646 dislikes jealous of this great video. Thanks for making it. One comment: I wouldn't want to risk putting the meter there while the car is starting, the surge voltage could damage it.

[@TaherHadidsaz]

This video helped me to trouble shoot my charging light issues. Even though the Alternator was bench tested good, the charging light was still on and I was not getting charging voltage at the battery. By using jumper wire from Alt B terminal to battery's positive terminal, the charging system issue was resolved. Thank you

[@JoeAse]

Good video. Very comprehensive in your explanations. However, never use a hammer directly on a bearing as it will shock load the bearing to cause premature failure from brinnelling. Use a bearing driver to absorb the hammer's impact and to drive the bearing square in the bore.

[@davebacknolaliki1452]

Can use a socket that fits on the diameter of the bearing too. I’ve done that and have had no issues with the bearing.

[@30YearOldBunta]

My car was overvolting like crazy and I suspect it's a bad ground. Thank you for such a detailed video, absolute perfection.

[@DonVTOL]

Best video on alternators I have seen yet!

[@psuitt]

I totally agree! The Junky DIY guy explains alternators perfectly.

[@royvilla5833]

Phillip Suitt I totally agree with you.

[@richardnolan9562]

Whoever narrated this did a way better job than the f****** school I went to dude you're awesome

[@commando7707]

I think my heart just grew two sizes larger to make room for Junky DIY guy.!!!!

[@mikespain8655]

This guy knows his stuff. Thanks, going to test voltage tomorrow on an old tractor with possible bad alternator.

[@mohabatkhanmalak1161]

Thumbs up, you are very good at what you do. In my teens, around 1980, I did an auto technician course at diploma level, which has come in very useful over the years. The modern vehicles of today are so much different, especially the electrics and electronic systems and require your kind of expertise. Keep up the good work!!

[@economist633]

Where did you do that corse?

[@economist633]

Course

[@mohabatkhanmalak1161]

@@economist633 It was a correspondence course at a polytechnic in the UK. I was living in Dubai at the time around 1980. Nowadays you can get these courses much easily on line, but look for good, proper institutions. Some can be bogus.

[@orleansadrianwhitakerarchb6422]

I HAVE TO SAY THIS HAS BEEN THE BEST CAR TUTORIAL I HAVE SEEN

[@andreasdrz1084]

Information in detail, no bullshit... Really good, keep it up!

[@luism.raposo5138]

Wow! I'm a mechanic and you my friend are very good at this. Good job. I subscribed.

[@niopress5162]

really appreciate the time and effort you put into making this video.your method of explanation makes it so easy to understand every detail.thank you so much.

[@ripalkumarpatel8817]

Excellent. In india mechanic knw that only one fuse is to replaced to repair alternator but they replace bruss and rectifier plate and so many things just to earn more from customer. ECM plays a good role for operating alternator. Good information share .Thank you

[@ajting3090]

You are a great teacher! Thank you. No hesitation here to subscribe. All the best to you!

[@Charliesvue]

It is a long video however you put so much information in it and it’s very helpful

[@angelzlatanovski5215]

You are an awesome man. Explained everything. Thank you, thank you, thank you Sir!

[@garylangley4502]

Very well done. You give good information, and your video is very professional. 2 thumbs way up from San Diego. I did not know about the decoupler. I learned about repairing cars in the early 1970's and they did not have decouplers then. A lot of my cars were so old that they did not use an alternator, but a generator instead. That BMW alternator is outrageous!!

[@JunkyDIYguy]

European car parts are expensive in many parts of the world due to the reputation as luxury cars

[@CORZER0]

Wow, I remember when your channel was only 24k subs! You're gettin pretty big, congrats!

[@JunkyDIYguy]

Thanks corzero

[@mgirano5822]

A great thank you from France. You are very fast speaking but I can understand with the subtitles. Your video is quite complete and it helps me much in my problem with my Honda FR-V.

[@hruaitea_elemel]

this is such a well made video.. exactly what i was looking for.. thank you for making amazing content

[@Cmn9882]

You are amazing, thank you for your time and effort to pass down this amazing knowledge. It is so perfect that it applies to 99% of vehicles

[@janicesmyth2183]

thank you for your great videos! I'm not a mechanic but learned quite a bit from your vids

[@AnotherDebtSlave]

Numbers for reference on AC leakage?? It's this kind of info that makes many subscribers. Thank you.

[@nothinghere2067]

A genuinely thorough and helpful video! Thank you!

[@OnTheCimarron]

Wow! That was quite replete. I honestly didn’t know there was that much to know about an alternator. I’m certain to watch this several times to absorb all the information. Thanks.

[@kareno8634]

W0W! Talk about Testing to depths I never knew existed! Thanks! . . . _now > to test my brain for efficient 'holding power'_ = )

[@mohammad45h]

سلام سپاس ودرود بیکران الهی بسیار متشکرم استاد مهندس گرامی وباشکوه وهزاران هزار 👍...👍...👍....بهترین ارزوها را از خدای مهربان برایتان دارم...ممنونم...👍.......

[@jessemerriman460]

Thank you for taking the time to put this together!

[@DONphantasmo]

this is one of the best alternator diagnosis videos on KZbin. Thank you!!!

[@PJM454]

Best DIY video I've seen on KZbin. Great job. Going to subscribe.

[@freestyleskyline]

Amazing, clear, concise and informative. Love the video man!

[@bobbyshaftoe]

So far [~20yrs] the best alternator vid on the t00bs

[@marknaylor6550]

Very very good, best alternator class ive come across

[@melissavaughn8724]

I've never seen such good tutorials. I'm so burn out before seeing yours idk if I can do it right now. I changed my battery once and alternator twice in my 2011 kia optima so I think it's not the alternator. Battery Volts drop after cranking it. Alternator rattles but the belt doesn't appear loose or damaged. Seeing this video I know to check the ECU. It's crazy I changed my alternator and battery but stumped on checking relays bc I have the cheap dial type. Also NONE of my instrument panel fuses light up and I think there's got to be a connection. You should charge a fee for phone support. Lol

[@jacobvance429]

Your videos are very well done. Thank you for the detail.

[@scottlanier5133]

My goodness one of the best instructional videos I've ever seen

[@huanweili7699]

I learned more information on here than in my Automotive class. Lol 👍👍👍👍

[@alekmartin9999]

Excellent video 👏 👏 👏

[@gr8zyco682]

good day, great video, informative clear detailed instructions, question, what reading to expect from the power connector that plugs into the alternator, i have a toyota/lexus 4 terminal connector alternator like the one in your video, im only getting a 12v reading from FR & L, 0v from IG & S connector terminals?.

[@Aikaramba12]

did you find out?

[@kevinsmith8516]

Excellent video, thorough and easy to understand explanation!

[@betgazal]

serious question, how many shops are actually going through this level of scrutiny to get to the root of it? this video makes perfect sense, and im wondering the best approach to having a probable regulator issue with my 18 colorado checked out without wasting time and money while someone putts around and just says oh, u need whole new alternator, yadda yadda

[@johnswilley6764]

Thank you Sir! Informative, succinct, articulate, and knowledgeable, also well produced video; without redundancy and unnecessary chatter. You are without a doubt among the best. I am now subscribed.

[@wilsonk]

Nice sharing my friend

[@TonyPablo]

Everything you need to know about automotive charging systems, great video!!

[@rossbrumby1957]

Thanks, that shed some light. Looks like an obd2 reader will be helping first on the lancer's overcharging in case it's the computer's fault.

[@nia6849]

Wow, best explanation ever straight to the point.

[@aubydauby]

This is the best video I've ever watched in my life

[@ricardoandrade7925]

You explain really good! Thank you!

[@godfreylubega795]

I keep watching this video and every time l pick a point. thanks, dude you are a genius,

[@claybourne7162]

Outstanding!! Thank you for taking the time to make this very detailed video!

[@lameckarika1949]

The best information I have ever got from any source. Thank u!

[@edgarsalinas6408]

good job , for sure one of the best videos outthere

[@69ztang]

Feels like I was in a mechanics class. Nice video and explanation.