Symptoms of bad or failing Alternator in your car | What happens when alternator in your car fails

This video provides some signs when alternator in your car starts to fail. Alternator is an electric generator in the vehicles to charge the battery so the vehicle get uninterrupted power to run the electronic accessories and the engine itself.

[@cliffords.8341]

I'm a retired motorcycle technician and machinist so I'm familiar with alternators as only a few motorcycles use an alternator. The majority use a stator mounted in an aluminum cover and magnetic rotor bolted to the crankshaft. When the crankshaft turns it creates AC volts that is sent to a unit called regulator/rectifier. The rectifier changes AC current from the stator to DC, then the regulator puts voltage in the battery based on what's being drawn from ignition, lights etc. A couple days ago my 2001 Chevy S10 started making a noise as if a bearing was going bad while driving, but not at an idle. I opened the hood and increase the engine rpm and I noticed the automatic belt tensioner appeared to to be working properly and it was hard to tell if the noise was from it or the alternator since they are only a few inches apart. Today on my way to work the tachometer jumped a couple times when it shouldn't have, then all of the sudden the engine shut off and the battery light came on, but the voltage for the battery showed just under 14 volts. I was able to get to work and I put a multimeter on the battery and the voltage was at 13.97, then all of the sudden it showed millivolts which is almost nothing. Luckily I have a spare alternator and belt tensioner so I will be changing them when I get home. This video explained that some electronics may not work properly including the tachometer when the alternator is not working properly which I was not aware of. Thank you for this video as it answered my question about my tachometer fluctuating. PS I will be subscribing to this channel for any future issues I might have to help me diagnose and repairs. Thanks

[@albytyqi1147]

I was driving and my heat on car stopped working after that my lights all turned off and after this i had my battery light on my dash board this video was so helpful i replaced my alternator and now everything works perfectly thank u very much for the video

[@dailyhandsdiy]

Happy to hear from you mate ☺️

[@ashfordfoster5676]

Very very very helpful thank you. Problem number 3 made all the since. Great video

[@robbygarate7414]

This was a very helpful video thank you !

[@paulstone949]

My 2011 ford focus titanium mk3 111,667 miles had the wrong alternator fitted when I brought it. Didn't notice until it packed up. Replacement parts are overly expensive.

[@marshallduncan787]

Great video! Thank you!

[@dailyhandsdiy]

Glad to hear from you mate ☺️

[@QuackVideo]

The first I knew I had a problem on my 2012 Skoda Fabia, with 190,000 miles on the clock, was when the Battery Warning light came on whilst driving through Knightsbridge.

[@Gboogie22]

My car started sputtering on WOT and had a rough idle, it turns out that one of the wires to the electrical connector attached to the alternator corroded and broke off.

[@kinfebiru2291]

thanks

[@godson1of1]

Very helpful

[@dailyhandsdiy]

Thanks bro

[@LubaLuba1]

I was able to replace alternator and battery with new ones but still not charging battery. I disconnect battery and engine turns off, I check with meter and reads 12.5 v with engine on but that's what the battery reads too so nothing higher when engine is on. Can this regulator prevent power or alternator from charging battery? On Town and Country 2011.

[@dailyhandsdiy]

Regulator is built into alternator and if its replaced then the regulator mist be new. Any loose wire, corroded wire can also do the same.

[@LubaLuba1]

@@dailyhandsdiy should I just put in a External Voltage Regulator kit for Dodge, Chrysler, Jeep, kit bypass PCM ?

[@Sweetnsassydee]

Hi They hooked up the multimeter at Auto zone, then I went to O’reilly too to make sure both said the same. Both times it passed everything except it failed voltage regulator. Do I need to tell my mechanic guy I need a new alternator or just a regulator?

[@dailyhandsdiy]

Hi, you just need new regulator. Don't have to swap the whole alternator.

[@Sweetnsassydee]

@@dailyhandsdiy ok, thanks for your reply!

[@Official_4Ten]

Question. My lights go dim on dash occasionally i rough idle....i replaced started because it would barely start now no issues except ones stated above. Whats some thoughts is it ny alternator?

[@dailyhandsdiy]

Could be a bad grounding, corroded wires or even loose connections.

[@vaughnkopacz2196]

is it normal to hear a clunking sound come from the alternator upon it's death?-my 2016 odyssey had this exact problem let alone it started on the freeway! the electrical would come on and cut off-is this all due to the altenator?

[@dailyhandsdiy]

Hi, looks like the alternator pulley has an issue especially if its overriding clutch pulley. Any loose bearing can also cause the same. Intermittent electrical cut might be of other causes, like bad wiring, loose contacts, corrosion in wires, bad ground, failing relays etc...any short in alternator can also trigger the same.

[@rasinbran8823]

I was coming to a stop and my car shut off and won’t crank you think it’s the alternator? If not any ideas?

[@dailyhandsdiy]

Firstly when the alternator fails, you should see a battery light on dashboard.eventualy the battery dies and engine shuts off. Check if the battery is strong and if yes, you have seized components ie, pulleys, bearings etc...

[@grantp4022]

Good video, can you help me ? I just had a new battery installed in my car. The reason was no power at all, even lights did not work. I ordered a battery, and this guy from the paper picked it up, and installed it, although I didn't see him do it, but the car was running fine after he left so I paid him. He gave me the receipt for the battery. Now about 4 days later, after I run my car for 15 - 20 minutes, and shut it off, the car is completely dead of power. Even the lights don't work and all my automatic settings, like clock etc, are not working. After waiting about 10 minutes, I can get a weak start. If I drive it a "short distance" and shut it off, it's ok, but if I drive it for 15 -20 minutes, it drains all power ?? and no power at all ?? QUESTION - did I get a bad battery and get ripped off by someone who installed an old used battery but charged me for a new one, or is my battery good, and thru the course of my 20 minute drive, is it the "alternator" that's not keeping the battery charged. Can you advise me on this ?? -- thank you.

[@dailyhandsdiy]

Hi it looks like the alternator is not charging enough. The guy who installed should check for proper charging. Also check the wire that connects the alternator and battery.

[@MvikheliElite]

Please help me.. my Polo Vivo cut off it's self while I was driving . I tried to start but not starting it only make click sound from the start,it doesn't start even if I tried to kick start , battery is good

[@dailyhandsdiy]

Hi, this could be a seize. Any pulley bearing or alternator bearing might or any other can get seize and stops the engine. Starter cannot spin the engine thats why it makes the click noise. This might be one reason.

[@Ennio-mq3d]

How about sound system… I mean like I have a sound system and when I’m playing it loud like 56 and my car stereo goes up to 62 my car wants to stall/shut off…BUT when I’m playing it to 33-36 the car does not shut off but it never showed me a battery light on the dashboard….what causes my car to shut off when I play high volume music

[@dailyhandsdiy]

Some high amp drwing sound system especially aftermarket drws high current at the time of high volume and this can cause temporary low voltage across the battery and high load on alternator which can further cause a disturbance in engine electrical systems. That might be the reason.

[@Ennio-mq3d]

@@dailyhandsdiy so it’s better to replace it with a new one to not cause more damages

[@akibsayyad2684]

Duster car alternator over heating please help

[@dailyhandsdiy]

Could be a bad regulator or burnt rotor.

[@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?

[@RiskRewardTrading1]

Yea

[@glenmccombs3916]

my battery light will come on and sometimes go off like it's come and off all the time i can't figure out what it is like i'll drive for 5-10 mins and the light will come on and then 2-3 mins later the light will go off it's weird

[@dailyhandsdiy]

Could be alternator regulator or loose power wires

[@hussainalajmi8604]

in my case were late start and low power in low rpm The problem solved by replacing the alternator

[@alexvvv1631]

Yeo Glooks broski I’m having tha same problem n I was gonna get a whole new battery

[@ichichao2733]

Is it possible that a bad alternator can cause O2 sensor to go off

[@dailyhandsdiy]

Havint seen that though...

[@72GiaGia]

I asked the same thing because my o2 went out then my alternator

[@AltruisticWarrior]

I have had chevys throw multiple lights when the alternator fails from traction control to TPMS or all lights. So... could.

[@mannykraft6824]

Just had the same thing happen to me

[@ayeeikeegaming2480]

​@@AltruisticWarriorthat's what my Cruze is throwing traction and stability, however last year when it threw them it was my battery 🤷🏾‍♂️ replaced w a used battery from another car and tested it days ago and it was good so cud be the alternator this time

[@rijulsharma4464]

Listen in mY car weak battery..so my ac compressor on and off ... After 10 sec. .or other Fault

[@user-gd8pd3be5l]

Alternator light on cloister

[@FortuneMakhoba]

I'm currently expecting a growling noise when car is idle and my windows are slowly functioning. Can replacing the bearings in the alternator solve the problem?

[@dailyhandsdiy]

A growling sound might be from too much load on alternator belt. A bad bearing makes a whining noise and increases with engine speed. If the growling noise increase when you roll up the windows, its likely the alternator is about to fail soon. Just bearings wont solve the issue, you might have a burnt alternator rotor.

[@FortuneMakhoba]

Thank you so much. There's no noise when I roll up the windows, it's just that they roll up slowly. So what happens is when the car is idle, that when I get that rattling noise.

[@dailyhandsdiy]

Alright .slow windows could be hardened glass guides. A rattling, clicking noise can be from belt bearings, alternator pulley etc...

[@preunit13]

Pretty easy to see if your alternator is bad. Turn on the vehicle let it idle remove the positive battery terminal. Of ot dies instantly, your alternator is bad.

[@MaCAttaK]

I thought you’re supposed to remove the negative?

[@dailyhandsdiy]

It's safer to remove negative

[@theaustralianconundrum]

NONE of these at all. Tested alternator and was fine.