Bad Alternator Symptoms

#shorts #motorcarnut
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[@cabewow6331]

Thanks for getting right to the point. Turns out the whining I heard was just my wife, alternator was just fine

[@Steven-te5xe]

Lol

[@Motorcarnut]

Lol

[@littlebigman5792]

Lol

[@BoltersBolts]

Lol

[@carlpoole3161]

😂😂😂

[@rypdx]

Thank you! Finally a video that gets to the point and doesn’t drag on 😂😂

[@Motorcarnut]

Thank you! Glad you liked it!

[@CDelly]

Fr

[@Masterchief0521]

this? I like this. no messing around, straight to the point

[@Motorcarnut]

Thank you! Appreciated

[@elppedro77]

Even easier, Check the voltage at the battery terminals, before you start it, should read 12.5 volts or slightly more. Then start it and check voltage again, at the battery terminals, with all accessories off, should read at least 1.5 to 2 volts higher (or slightly more) than the voltage before you started it.

[@Motorcarnut]

Correct!

[@fernandoaviles6759]

Sr, if you can help, my 05 mustang gt is 12.6 volts before starting the car, when the car is running the voltage is 13.7, with all the accessories it seats at 13.4 volts. Would you recommend for the alternator to be replaced?

[@Motorcarnut]

@fernandoaviles6759 No, seems normal

[@fernandoaviles6759]

@@Motorcarnut I thank you for the prompt answer, yesterday the car stall while I was driving and then it would crank but not start, now that I can disregard the alternator I will move to replace the crankshaft sensor since there are videos which state that could be the culprit, I appreciate your help.

[@elppedro77]

@@fernandoaviles6759 No, sounds about right.

[@wxxregta8388]

Bro my alternator screams like a supercharger and it’s been working just fine for me

[@Motorcarnut]

That’s not good, should replace it before it fails.

[@wxxregta8388]

@@Motorcarnut probably but I’m not going to😂

[@CommanderRich]

@@wxxregta8388don’t wanna end up like me and it drains the battery and you can’t even unlock your truck 😂

[@skinnysizmygame]

That means your alternator got bad bearing screaming like a hellcat

[@eerqv]

@@CommanderRichI have a Infiniti coupe and my windows won’t go down enough to close the door

[@marlowcalles9088]

Thanks man js gave me more info and straight to the point love it

[@Motorcarnut]

Sure, no problem! Thanks for the response

[@mymusic3354]

My alternator was doing all sorts of crazy things, random electrical gremlins, then there was a high pitched whine through the stereo speakers, instrument cluster lights would all pop on while driving, then go off, gauges would flip out then go back to normal, stereo would shut off and come back on and shut off and come back on, the air bag light would randomly dimly be visible.....The voltage meter in the truck would fluctuate, then the "battery light" flashed on and off a couple times and I was getting no charge, so I checked the charging system and got a no charge result, which confirmed the alternator finally completely gave out. So I got a new alternator and a new battery and put them in and Voila! Everything is great. Also, when I pulled the alternator out, spinning the pulley on the front of the alternator it was making some loud squeaking sounds 🤔 I'm actually glad it was just the alternator, I was thinking it could also be a bad ignition switch but everything is great now.

[@Motorcarnut]

Good the hear that great that it helped!

[@mymusic3354]

@@Motorcarnut Yeah the vehicle was doing a lot of strange things and I wasn't sure what was going on, turned out the alternator was causing everything, so I replaced it, everything works fine now. I also put in a new battery to go with the alternator so everything is new, when out of the vehicle the pulley squeaked pretty loud, it was pretty old and finally got around to changing it, there also was a smell that almost made me think oil leak but that was the alternator too apparently, because there is no oil leaking and the smell is gone. I checked everything else under the hood before zeroing in on the alternator, couldn't figure out why it smelled like an oil leak when nothing was leaking, I didn't know it could be the alternator, sure enough it was. 😂

[@dkt1976dt]

I had the same issues on my car, it was the wiring from the ignition switch going to the alternator. The alternator wasn't getting power or getting sporadic power causing all sorts of electrical issues with my car.

[@mymusic3354]

@@dkt1976dt Yeah, I spent time checking all the wiring and grounds, fuses, fusable links and relays first, resistance checks on the wiring, checking all connections first because the alternator wasn't making noise and I knew it was possibly a wiring issue somewhere, didn't cost me anything to check all that stuff first, but everything checked out and it was narrowed down to the alternator which only took a few minutes to swap in a new one, put in a new battery at the same time....I was actually relieved to find the wiring and everything else checked out, since a lot of the wiring and grounds wrap around and wind through spots where a person would have to remove a lot of parts to get the old wiring out and the new wiring in. I definitely checked all the wiring though (initially suspected that could be the issue and wanted to rule it out first) The alternator was going out and eventually died completely, it was pretty old though so it wasn't surprising that it eventually went out, it was a really simple replacement which is always nice 😁

[@Motorcarnut]

@dkt1976dt sure that would do it for sure.

[@bluor3713]

Informative video, straight to the point. Refreshing. I subscribed

[@Motorcarnut]

Thank you for the sub and comment!

[@jamielamie2229]

great info, i have a feeling my alternator is gonna have some issues soon 😭😭 its not taking all this heat too well

[@Motorcarnut]

Thank you, yes especially if you smell it burning. The windings inside start to deteriorate when that happens

[@DubTheG]

What if I shake the alternator while I'm holding it, and it kinda rattles?

[@Motorcarnut]

I would say something is wrong with it and would get a new one.

[@bruceli9094]

Could be gold nugget you accident picked up driving

[@dkt1976dt]

Sounds like the bearings are gone.

[@UltimatumDemon]

What about the ground from alternator to block? Wouldn't that affect the 13.5V

[@Motorcarnut]

Rare but it can, starter is already grounded to the transmission case

[@MOONXXVI]

🙋🏽‍♂️I have a question, my timing cover is leaking oil onto/into the alternator (1zzfe). I think its causing electrical issues. My question is could i clean the alternator without damaging it until i can repair the oil leak?

[@Motorcarnut]

Most likely, first disconnect the negative battery terminal then use electrical cleaner on the electrical part of the alternator and if you have compressed air blow it dry or just let it dry about a half hour then reconnect battery.

[@Nuxalkman]

Going through alternator stuff right now, my friend had a digital tool that isolated that it is the alternator not working correctly but I kind of figured it was the alternator, stalling out, dimming lights, stalling. Brand new alternator ordered, have it in a few days

[@Motorcarnut]

Should fix you problem

[@newtonraymond77]

How do you get voltage when you put your ohm meter on it? That's crazy talk

[@Motorcarnut]

I said it wrong, sorry

[@limited50scla]

Mine took a crap yesterday…. It thought that winding sound was from the 350 Vortex engine in my 2000 Tahoe Limited. Didn’t notice it was completely shoot until it was making a weird winding noise and it started to smell like burnt rubber or coal or some weird. The obvious was voltage drop while driving. Not my AC joined it, it would normally make noise when the Clutch would engage, now it does it all the time.

[@Motorcarnut]

Better replace both at the same time because the ac clutch can lock up and snap the belt and leave you stranded.

[@Pinkaddictionnn]

My car had screaming sound. A mechanic said is was the ac compressor but i disagree. It wouldn’t start anymore after awhile, i replaced the battery then the car started for like five minutes now it won’t jump start without blowing ignition fuses. Can all that be from the alternator ?

[@Motorcarnut]

Starter, or alternator yes.

[@adriannewman1322]

Sometimes the alternator is fine and it just needs the decoupling pulley replaced. That's what happened to my 15 journey

[@Motorcarnut]

That's kinda rare but yes that can happen. Thanks for the feedback!

[@Adrian-qx4ql]

Not every car has a decoupling pulley usually alternators last 5 years that's a good benchmark

[@Motorcarnut]

@Adrian-qx4ql No, more than that

[@a.kblur04]

mine makes noise when it wants to, had it tested and everything seems fine. no other symptoms, sometimes is smells burny sometimes it doesn't. i have a reman ready for when it goes bad lol

[@Motorcarnut]

I’d replace it before going far with the vehicle.

[@a.kblur04]

@Motorcarnut was going to yesterday but then i pulled the cap off the pulley and cleaned the pulley out, now it's silent and it passed a voltage test with flying colors so idk

[@Motorcarnut]

@a.kblur04 ok, so not yet, good saved money

[@guesswhomartin9249]

Yeah, that was the same thing I had with my alternator, I replaced it anyway. I didn't want to take that chance.

[@Motorcarnut]

Alway good assurance.

[@christophermitchell2350]

Thanks my man . Great stuff . Nice accent too.

[@Motorcarnut]

Glad you enjoyed it! Appreciated!

[@scotthendrickson8509]

Best video ever 🙌

[@Motorcarnut]

Really appreciated!

[@majindrixz965]

Does that mean why my windows from the back only go down and not the front ones ? can’t be the battery right ? I Berly bought a gold dura battery 🔋 from auto zone

[@Motorcarnut]

No, that’s related to the switches or the power window motors or wiring.

[@jesseb4827]

If it “whines” “squeals” only during cold start, does that mean it’s the alternator? I changed belt tension pulley and idle pulley and still screeches

[@Motorcarnut]

Usually squeals and screeching is a belt slipping but being you changed them, yes the alternators bearings can make that noise too.

[@ayden8901]

I’m trying to troubleshoot if it’s my alternator or starter. Doesn’t always start the first try, starts rough, sometimes when it starts it’ll rev up and down before it settles while idling. When driving there in a whine. I’m hoping it’s the starter since that would be cheaper but I’m thinking it could be the alternator :(

[@Motorcarnut]

Starter won’t make a whine while driving that could be the alternator. All the starter does is start the vehicle has nothing to do with how it runs .

[@dominicschwartz1917]

Literally just changed mine last week

[@mikenonhuman1335]

Thanks

[@Motorcarnut]

No problem

[@danielbeckstead-xk8md]

I heard in a video about car care and repairs that you can also check it out to see if it is good or bad by sticking a screwdriver to the back of it to check if it will magnetically stick to it and if it does stick than it's good if not than change it out....

[@Motorcarnut]

That doesn’t say much about the output of the alternator.

[@peterrudy9207]

I suspect it is bad on my 2020 Toyota Camry . Possible cause that i had used the double the amount of soap and rinse cycle at the self serve carwash . As I have never covered it with a heavy duty plastic bag , etc. I will routinely do this everytime now .

[@Motorcarnut]

Yes, it has diodes in there that will blow if the get really wet. Check voltage from red lug on alternator and ground with car running should be 13.5 and over.

[@peterrudy9207]

@@Motorcarnut Ok , though I bought already the block fuse for the alternator to replace . And removed parts to get to the old , to replace it . Will know if that was blown when it's removed . And after watching a video , I can easily replace the alternator .

[@Motorcarnut]

@peterrudy9207 great! Thank you!

[@Purpatratur]

I had my car sit for a while with the batteries still in it. I had it recharged. the car started but no lights on the dashboard and some inside my car I replace all of my fuses and now I’m convinced it’s the alternator because it was whiny and losing power

[@Motorcarnut]

May very well be!

[@johnathoncastro]

My alternator is covered in oil from and oil leak. It's black. Will that eventually kill it? the leak has been fixed.

[@Motorcarnut]

Yes, liquid and electrical don’t mix. It you have access to an air compressor you can try to spray it with electrical cleaner and compressed air, make sure you disconnect the negative battery terminal Before you clean it.

[@TheHilariousGoldenChariot]

No oil does not conduct electricity and the additives in the oil are very minor so they should no be enough to create some sort of short.

[@JoshSmith-wo7zw]

​@@TheHilariousGoldenChariotWrong oil attracts dirt and dust which causes overheating of the windings in the alternator.

[@TheHilariousGoldenChariot]

@@JoshSmith-wo7zw that is good point

[@JoshSmith-wo7zw]

Oil will attract dirt and dust causing the windings in the alternator to overheat. There's a good reason for the grooves in the case exposing the windings. There for heat dissapation. Dirt and dust act like an insulator. I/E prevent heat from.dissapating.

[@imgonnagogetthepapersgetth8347]

Yes on the voltage BUT!! Not always!!! I just went through this on a Camry. Burned out 5amp fuse labeled "AM1" in the fusebox at the driver's left knee area somehow doesn't allow the alternator to put out voltage. I guess when it is burned out, the alternator doesn't get a signal to put out voltage. Also, if you take off the cable from that lug you pointed at, and run the engine, that lug will put out like .5-1volts. It needs to be connected, and your fuses must be in order. I was only getting battery voltage at that nut, and thought my alternator was bad. Advance Auto bench test misdiagnosed my alternator as bad, too... I had other issues, and found the burnt fuse, replaced the fuse and now get 14.x volts.

[@Motorcarnut]

I didn't say, take off red power cable to alternator lug, leave it on and car running when testing. This video is about bad alternator symptoms, your vehicle obviously had many other issues not covered in this simple short clip. But thank you for the extra info, may help others!

[@user-hq7ff6kx6b]

Hello, is it possible to hear grinding noises from the alternator only when the AC is on and the car is on idle? Thanks!

[@Motorcarnut]

Possibly but could be the ac compressor too

[@user-hq7ff6kx6b]

@@Motorcarnut the mechanics told me that the alternator bearing is blocked in the both ways and that's why I am wondering if this could make a noise on idle and ac on

[@Motorcarnut]

@user-hq7ff6kx6b it’s hard to say, if that is what the mechanic thinks then it’s not unheard of.

[@Adrian-qx4ql]

My car was making a horrible grinding noise alternator just went out I'm getting it replaced it about 4 days I hope it was that cause if not my transmission is done

[@Motorcarnut]

@Adrian-qx4ql A bad alternator can cause many problems.

[@matthewsones5287]

Unless it’s a one wire you’d need to check the exciter wire for battery voltage

[@Motorcarnut]

Good tip!

[@relaxingambientsounds7365]

Where is the exiciter wire

[@LJT9393]

@@relaxingambientsounds7365check your pants

[@budwhite9591]

My alternator fried my battery. I got a dash light “check charging system”. 15 minutes and 10 miles later car was dead. No flashers, no door locks, couldn’t even pop the trunk. Dead.

[@Motorcarnut]

Yes, Iv'e seen that happen a couple of times.

[@valenzuela7298]

Mine was whining, I had just done my belts. I think I tightened it up too tight. I loosened it up not too long ago now I hear it ticking sound, and I just experienced a bad alternator car stalled out no power juiced up the battery dim lights gave me a couple check, engine lights, including speed sensor, it just tripped out the whole system

[@Motorcarnut]

Yep, people don't realize its the alternator that keeps the car running, not the battery. The battery is only to start the car.

[@jpbates8694]

I replaced alternator, ac compressor, condenser, belt tensioner, power steering pump and belt why do I hear like a groaning sound. Especially when I turn my ac on and the car is idle

[@Motorcarnut]

I don’t know what vehicle you have but , just take all belts off and start vehicle see if noise is still there, if it is then it’s probably the timing chain slapping inside the engine.

[@jpbates8694]

@@Motorcarnut thanks for responding I have a 2011 Buick Lacrosse 3.6L Cxl

[@Motorcarnut]

Ok just do what I said

[@anthonyarroyo2672]

Do you do this when it’s on?

[@Motorcarnut]

Yes with the car running and a volt meter not ohm like I said that was incorrect

[@donparrish5634]

What if I use my volt meter to check the voltage ? Or should I use the Ohm meter still ?

[@Motorcarnut]

Sorry I meant a multi meter which does both

[@hectorguillen3511]

It's bad when smokes 💨 comes out of it from my experience and your car dies 😐

[@Motorcarnut]

That’s extremely bad

[@TheTruelakersfan]

You forgot to say while the car is running

[@Motorcarnut]

Well the alternator puts out voltage when the vehicle is running, common sense but thanks for the comment. Maybe will help someone out.

[@cd4917]

My check guages light came on and my voltage guage ws on the low side. I heard a really whiney noise soopped thw hood and there is whit e smokw coming out of my alternator😮

[@Motorcarnut]

Yep it’s gone

[@cd4917]

@Motorcarnut yep sure was toasted lol..I put a new one in with a new belt and good to go. Thank you your video helped me get the job done, peace of cake!

[@Motorcarnut]

@cd4917 awesome! Take care!

[@mushy18100]

Can I test using the volt meter if the car is currently hooked up with another car so the bad car is starting ?

[@Motorcarnut]

No, that will be inaccurate.

[@romecottrell]

My alternator is is charging lower than it should and whines. I know it needs replaced. But what causes the low charge and whine?

[@Motorcarnut]

Many things inside the alternator can cause this, a bad stator, diode regulator etc

[@JohnDoe-mt8rf]

Question - I have smoked 2 alternators literally and it gets hot very fast and I cannot figure it out? My starter is new my battery is new and positive and negative are clean. It's a Cadillac DeVille 1992 with a 4.9.

[@Motorcarnut]

Can be a short in the wiring somewhere. Corroded ground or battery wiring internal like very hard to bend. Or excessive draw from somewhere like high powered stereo amps for example.

[@JohnDoe-mt8rf]

@@Motorcarnut I have the original radio. I took it to a mechanic and he put a new alternator in it and it works and doesn't smoke or get hot but it kills my battery every 3 to 4 days , weird.

[@Motorcarnut]

@JohnDoe-mt8rf That is. Could be that new alternator?

[@thatwasquick8829]

Thank you for the ℹ️

[@Motorcarnut]

No problem!

[@michaellaforte6964]

Anyone ever heard of the alternator bearings going bad?

[@Motorcarnut]

Absolutely

[@michaellaforte6964]

@@Motorcarnut I would assume it would give a sound like you’d expect from bearings going bad, which is not the high pitch whirring sound but more a grinding sound, correct? I’m trying to determine if the mechanic at the stealership is gouging me, which I suspect

[@Motorcarnut]

@michaellaforte6964 either way an alternator can make both sounds if the noises are coming from it.

[@Adrian-qx4ql]

​@@michaellaforte6964my alternator went bad prior to that the car would make these horrible grinding noises

[@MrEd-eo3oc]

Made a mistake in this. “At least 13.5 volts”. Nah bro, I had an alternator giving me 17+v for a 12v system. That is bad 😂 what you are looking for is between 13.5-14.7 at 1200rpm

[@Motorcarnut]

Hence at least 13.5

[@MrEd-eo3oc]

@@Motorcarnut 🤦 that doesn’t account for OVER VOLTAGE. You’re welcome

[@Motorcarnut]

@MrEd-eo3oc over charging is rare but it does happen. So this can be helpful as well. Thanks

[@MatthewNelsondbz]

My accord says it has overvoltage that’s what my obd scanner is saying is the only issue, I did put in the v6 battery of the same model but mines the 4 cylinder, I’ve seen people do the swap and be fine but my alternator says overcharge at 14.7 volts

[@Motorcarnut]

It's not the battery. Probably a bad voltage regulator inside the alternator. Should replace the alterator asap unless the voltage regulator is replaceable by itself. It will destroy the new battery you put in.

[@danielmelendez9943]

What do you mean by whinning? Cause when my acura is on, i can hear a whinning noise and i thought it was a pulley or a belt rhat was dry and needed lubricant

[@Motorcarnut]

Usually that’s a telltale sign the alternator is on its way out. But spray the belt with belt dressing and see it the noise goes away.

[@user-rk8np6ty2x]

What if my pulley wobbles is it just the pulley from alternator or do I have to replace the whole alternator??

[@Motorcarnut]

Depends, try tighten it. Don't know how it can wobble unless the alternator bearing is blown.

[@jayjones8424]

It's been whining and lights flickering in my car if it finally went completely out will my car not start at all

[@Motorcarnut]

Yes if the battery is weak because of the alternator.

[@jayjones8424]

@@Motorcarnut surprisingly not the alternator got it tested at orileys but wonder why all my lights flicker😑

[@Motorcarnut]

@jayjones8424 got to check for loose or bad ground wires and make sure battery terminals are clean and tight

[@JoshSmith-wo7zw]

Its only going to show voltage with the engine running. If you have cables attached you'll get battery voltage without the engine running. With the engine running it should be around 13.5 volts but keep in mind some newer vehicles don't have voltage regulators in them. Instead its controlled by the computer and the voltage can drop below 13 volts at times and it doesn't mean there's something wrong with your alternator. The computer just shut it off for whatever reason.

[@Motorcarnut]

Good points

[@davidhammond8098]

Ohm meters show voltage?

[@Motorcarnut]

Sorry when I said ohms I meant mutimeter.

[@JReiid]

I have a 1998 Celica and have had a whining for over a year now. Have replaced the entire alternator and the belt and still have it. It gets dramatically worse when the engine is under load (such as revving) or if the rear demister is on, electric windows going up etc. What is the problem? It’s driving me insane.

[@Motorcarnut]

Could be your timing belt

[@JReiid]

@@Motorcarnut Never heard of a timing belt making any sort of whine. It’s only got 30k miles on the belt

[@Motorcarnut]

@Mw2JaCkJRR if it’s too tight or has a bad pulley it can,

[@JReiid]

@@Motorcarnut I think the fact it gets louder under load and with accessories on such as rear demister, lights etc points to it being alternator related but thanks anyways.

[@Motorcarnut]

I don’t have the car in front of me to tell you exactly what wrong with it just your explanation. You said you replaced the alternator and same whine so idk

[@pitbullisaac]

I was driving i heard like a high pitch sounds coming from the hood , and loss power at the red light did want to go then after 10 second it went fine then i turn it off and it didnt want to turn back on, i could hear the car click when i crank it

[@Motorcarnut]

Could be the alternator belt too if it’s too loose or broke. Then the car runs off the battery till it dies.

[@Puffdaddyxxx]

@@Motorcarnutbut wouldn’t the car be over heating since the water pump is ran by belt also? Or am I mistaken?

[@Motorcarnut]

@@Puffdaddyxxx No because the belt that drives the water pump is seprate from the serpentine belt

[@samaden7869]

​@@Motorcarnutnot in all cars. Toyotas and Lexus run water pump and all accessories with a single serpentine belt.

[@Motorcarnut]

Depends on what years, models and engines. Some do, most don’t run off a serpentine belt, a timing belt not serpentine.

[@Sdcalip]

Other than that, thanks for the tips

[@Motorcarnut]

Thank you!

[@j.bxndz8239]

What can cause the whining?

[@Motorcarnut]

The serpentine belt or the alternator itself.

[@nanhand99]

Yep, mine's bad Thanks 👍

[@Motorcarnut]

Sure, no problem!

[@aaaaaaa-cy3qg]

At Auto zone they tell you for free when is bad so go to auto zone or Auto parts and is easy and quick

[@Motorcarnut]

Sometimes the vehicle won't start or run enough to make it to an auto parts store and sometimes people want to learn themselves as well.

[@cappy007]

My alternator sounds like it’s scratching a chalkboard. I bought a replacement just in case. Thoughts?

[@Motorcarnut]

Could be on its way out. Good call on getting a replacement!

[@gradyrm237]

Meter on Ohm's will get you a voltage reading???

[@Motorcarnut]

No, sorry meant muti meter on dc volts

[@brandonmorals4239]

What about rattling whenbi turn the ac on and shaking when the ac is on ?

[@Motorcarnut]

Could be idle control is not working when ac is on.

[@brandonmorals4239]

@@Motorcarnut what can cause that an what can I do ?

[@LilyWillow22]

@@Motorcarnut how can that be fixed?

[@Motorcarnut]

What are we talking about?

[@DrSpray-yk9ru]

Can you try to upload the whining sound how it looks like PLEASE ??

[@Motorcarnut]

I don’t have any vehicles at the moment with that problem but sounds like a power steering noise.

[@Michael-db4sn]

My 09 highlander has electric power steering but its making a power steering noise. So its a bad alternator. Yesterday i lost power steering and brakes while sitting in traffic and all dash lights came on. New alternator on order.

[@edswrld]

How do you inspect whining

[@Motorcarnut]

You listen for it

[@Yatta760]

I just bought a chevy impala 2001 3.4 and it sounds like and Rc car well whine and the battery dies and everything but the guy I bought it off of put a new alternator in it could it be a bad alternator

[@Motorcarnut]

If the whine coming from the alternator, yes

[@Yatta760]

@@Motorcarnut thank you I’m goin to replace the battery and alternator the battery is old but the alternator is brand new i was driving the car for like 15 mins the battery died and a whine sound coming from the alternator I believe an battery went completely dead it wouldn’t stay charge

[@Motorcarnut]

@aiyonslifestyle1371 Also if the battery was that bad, just change the battery first and see if the whine goes away. The alternator may be whining because it’s over working because of the bad battery.

[@thejoshno]

My car is running at 15.2 volts. 2012 Cadillac cts. Probably the voltage regulator is bad?

[@Motorcarnut]

Correct!

[@thejoshno]

@@Motorcarnut I replaced the battery and all the dash lights went off. Old battery had a bad cell and was 6 years old so it was causing issues. Since I commented everything went back to being normal. But thank you for the video it was greatly informative now I know what to look for in the future.

[@Motorcarnut]

No problem, thanks for the update!

[@qunicetoole7497]

car stereo has whining noise and must be the alternator

[@Motorcarnut]

It’s the stereo if it’s aftermarket and doesn’t have a noise suppressor

[@johndoherty7993]

Mine alternator wines when I drive should I get it replaced

[@Motorcarnut]

Yes, that is one sign of starting to fail.

[@TheSteve6489]

I have a 2008 sierra 5.3 the battery meter fluctuates and drops, but doesn’t go under 12v now my Soundsystem has no power. Could it be that my alternator does not have enough power? I have no other symptoms

[@TheSteve6489]

My whole system is aftermarket. Alpine double din, 1200w fosgate amp, 2 10” fosgate p3’s, infinity kappa 6x5, 350x4 fosgate for highs and a 800 agm battery. Any advise will help thanks.

[@Motorcarnut]

Absolutely, the alternator is not designed for that much extra load and can’t keep up. Best bet is to get a high output alternator. I myself had high end sound system and that’s where you have to start. Also make sure you have ground strong grounds 4 gauge minimum to and from alt and chassis. Positive side should be beefed up as well.

[@TheSteve6489]

@@Motorcarnut Awesome will upgrade to a high output. Thanks for the info!

[@Motorcarnut]

@TheSteve6489 no problem!

[@Psp-id7uw]

Can it throw off of abs then abs to limp mode and limp.mode to solenoid codes

[@Motorcarnut]

If you have solenoid codes you have to diagnose them first.

[@Psp-id7uw]

@@Motorcarnut hard laggy shifts at a " regular" speed and it throws solenoid d code... if accelerating at a quick speed all shifts are smoother and no engine code I've been clearing the codes soni can continue driving. Shouldn be doing that. Mech diagnosing soon

[@Motorcarnut]

@PEsp-id7uw I would replace the valve body with the solenoids and you should be fine.

[@Psp-id7uw]

@@Motorcarnut damn lol...

[@twitchkillgod2985]

Thanks boss

[@Motorcarnut]

Sure, no problem!

[@GODZREAP3R]

Mine completely broke would turn counter clockwise but would free spin clockwise 😢

[@Motorcarnut]

Something internal broke

[@James_Edward59]

That’s with it running, what if you can’t get it running?

[@Motorcarnut]

Take it out and bring it to an auto parts store they test them for free.

[@demo2382]

With key on engine off the post at the alternator is +12v but when the engine is running the post at the alternator is -12v. I have no idea why its putting out negative voltage

[@Motorcarnut]

It’s shorted out, replace it

[@demo2382]

@Motorcarnut okay I'll exchange it. It's "brand new" as well lol.

[@joey3032]

I’ve heard this can be typical. Poor manufacturing regardless of price paid. I needed this video and comments to help steer me. My issue seems to be intermittent. Which leads me to think bad ground or broken wire somewhere. Checked all fuses but not relays yet. I fear a parasitic draw may be possible also. So many tests so lil time 😫

[@demo2382]

@joey3032 forgot to reply to the other guy, but I ended up replacing it, and the problem went away. It's always at +12v now with both key on and running. Just a bad "new" alternator.

[@Motorcarnut]

@joey3032 let me know how you made out

[@Bella-uy6lc]

Mine is not charging my battery. I had it tested,i was told it was shooting 13 volt.that it was bad.i have bumper to bumper warranty on my car. Its a 2020 hyundai elantra se 18,000 miles.what do u recomend? Please reply a.s.a.p🙏🙏🙏

[@Motorcarnut]

Should be over 13.5 volts minimum when running, just take it back for them to replace it under your warranty it should definitely be covered.

[@Bella-uy6lc]

@@Motorcarnut thank you very much

[@Motorcarnut]

@Bella-uy6lc No problem, good luck!

[@Bella-uy6lc]

@@Motorcarnut it turned out to be the battery and it was covered by the warranty. I am so happy jiji

[@Motorcarnut]

Glad it worked out! And thanks for the update, was curious.

[@FastlifeDee]

What if you jump start your car and then after a while it turns off?? When i had it on after the jump it read at 14.2 but once i turn it off it wont start again

[@Motorcarnut]

The battery is bad

[@zaidmunzir1116]

Alternator has 13.5v and then it drops and comes back after sometime. Is it an alternator issue?

[@Motorcarnut]

If you’re testing it from alternator itself, then yes

[@zaidmunzir1116]

@@Motorcarnut hmm ok. I’m assuming you know A bit about cars. The AC went out and stopped cooling around the same time and the battery light came on. Is it related to the alternator or could it be something else?

[@Motorcarnut]

@zaidmunzir1116 You can have the alternator checked by local big chain auto parts store for free. I’m not there to diagnose the vehicle.

[@82_KID]

What if your alternator is just bad? lol

[@Motorcarnut]

This video helps people decide

[@zo4199]

I installed a new alternator and belt on my 2012 corolla Belt config is correct, alternator generates electricity and recharges battery The issue is that when I give the car some gas the electronics flash and turn on and off I got that duralast gold alternator Any help?

[@Motorcarnut]

That sounds like a bad ground wire. Make sure they are all solid and not corroded.

[@zo4199]

@@Motorcarnut It was dirty, I cleaned it and it's running perfectly fine now, thanks man!

[@Motorcarnut]

Awesome bro! No problem

[@bryantreddy3288]

When you say whining, does that mean it’s making a noise when you press on the gas pedal? 🚨🙋🏾‍♂️🚨🙋🏾‍♂️

[@Motorcarnut]

Yes, that too.

[@Cm1sDodge]

Don't you means 13.5 v? ohms shouldn't show up on that test

[@Motorcarnut]

The meter is an ohm volt meter, but your checking for voltage

[@georgesrisomsak9650]

​@@Motorcarnut it's called a multimeter.

[@Motorcarnut]

I know what’s it’s called, most people don’t

[@denzelcrocker4956]

Hey, mine is whining when reving. Now i got the altenator out, but i dont know how to control the bearing. It Sounds smooth when Spinning

[@Motorcarnut]

Sometimes you need a load on the bearing to make the whine so it’s probably bad anyway.

[@denzelcrocker4956]

@@Motorcarnut thanks

[@Motorcarnut]

@denzelcrocker4956 sure, no problem

[@josephbavone3619]

ohmmeter means resistance. voltmeter tests volts.

[@Motorcarnut]

Correct and multi meter means more

[@yanisyns6427]

Can anyone help diagnose a problem I have with my 2013 VW Jetta 2.5 SE. The car was sitting for 4 months at a body shop and when I picked it up from there, I turned it on and after driving half a mile, I could not accelerate, all my dashboard lights came on and the car died and would not turn on. I replaced the alternator (twice) and battery and I am still having the same problem. The mechanic is saying it could be the alternator fuse. I bought one and waiting on it to arrive. Does anyone know whether it could be the fuse or could it be something else?

[@Motorcarnut]

Sounds like an electrical problem, the local mechanic should be able to troubleshoot it for you if they are competent.

[@urbexnation7656]

My alternators at 2.4-2.7 is it ok ish?

[@Motorcarnut]

What do you mean 2.4 2.7??

[@Josuev1902]

If my battery dash meter is moving while driving and losing power is it the alternator?

[@Motorcarnut]

Best way is to test the alternator with a volt meter. Put positive lead to alternator big lug and the negative to the battery, with engine running at idle it should have over 13.5 volts. Also make sure your battery terminals are tight.

[@logoTMM]

What your ... volt meter or Ohm... meter...

[@Motorcarnut]

Sorry meant volt meter.

[@un1on776]

I have a little problem, the car is working at 800rpm and when i turn lights and ac on it drops to 500 or even less, I tuned the car to idle at 1100 and when I turn on the lights it drops to 800 or 700, the alternator is charging from 13.6 to 13.9v, what could be the problem?

[@Motorcarnut]

The alternator is probably good. It can be the idle up motor, or idle air control is another term for it. It mounts on the throttle bode and can be cleaned with carb cleaner. IT’s responsible for raising the engine idle when there is a load such as turning on the AC etc.

[@willemdaniel4213]

What if it’s violently throwing sparks and sound alike a bucket of bolts

[@Motorcarnut]

Replace it immediately!

[@xavierrichards3749]

I just entered the highway trying to pick up speed and all of a sudden I see white smoke in my rear, the car slowly loses speed, I pulled over and popped the hood and it was light smoke near where the alternator was. My car won’t start all you hear is rapid clicking sounds, sometimes when it does turn on for a couple of seconds before turning off, you hear like a knocking noise almost like it’s banging, What might that be??

[@Motorcarnut]

Sounds like you blew a head gasket or the engine.

[@samaden7869]

Alternator went bad, didnt notice, seized serpentine belt, water pump stops working, engine over heats. But in this case youd have known because your steering should have been stiff. If serpentine is still connected, your alternator prolly blew out and the battery went flat after powering fans and other accessories. But then, the white smoke is definitely coolant leaking into the combustion so like op said, gasket blown in easier scenario and might as well still be alternator since other sensors and components don't get power, engine blown in worse scenario.

[@hector10908]

If I get the alternator replaced what other items should I also get replaced? Like belts, tensioner etc,. 2006 Nissan Sentra 1.8L

[@Motorcarnut]

The alternator, belt and the tensioner is a great start.

[@Dude_Ness]

welp, guess i need a new alternator

[@toxicSuperstar_762]

Uhh read with the engine running or no?

[@Motorcarnut]

Engine running

[@amyk9813]

Do you use the voltmeter while the car is on or off please?

[@Motorcarnut]

When it’s on to check alternator output

[@joey3032]

@@Motorcarnutsorry people keep correcting your terminology. Your video was pretty straightforward for what it is. I didn’t need 20 hours of learning how to turn my multi meter on and off , what a car is , how to pop the hood and 30 advertisements for eczema or irritating bowel syndrome in between. I was looking for exactly what you put up. So thank you.

[@Motorcarnut]

@joey3032 Thank you! I really appreciate that!

[@VioletBugge-sr8oh]

What if you test the alternator with a battery tester and it jumps around between 12.3v and .5v

[@Motorcarnut]

Bad internals in alternator

[@bluffa4ve]

Point is.. your alternators bad.

[@Motorcarnut]

This is to make sure it is.

[@vulcandawg7623]

Would loud squealing on start up and dim low beams be a sign of a failing alternator

[@Motorcarnut]

Absolutely

[@vulcandawg7623]

@@Motorcarnut oof... well... at least its a cheap price part... and will be easy for me replace... thanks my dude

[@Motorcarnut]

@vulcandawg7623 sure no problem

[@hunteradams859]

Why does it whine for could water getting into it it

[@Motorcarnut]

Usually it’s failing bearings

[@erick-om6sm]

Mine turns, it whines like hell. It test over 13.5... is this super urgent repair or can i wait a second.

[@Motorcarnut]

Whining means it’s on its way out, can’t guess how long though.

[@kenchevy3960]

Did that test with ohm meter was not a bad alternator there was a broken wire in a large harness by the transmission

[@Motorcarnut]

Good diagnosis

[@jerramiemiller]

what if it spins freely but sounds like something is scratching on the inside?

[@Motorcarnut]

Depends, can be a bearing or other defect