How to Tell if Volkswagen Needs New Alternator

By Product Expert | Posted in Tips and Tricks, VW Service on Wednesday, January 25th, 2017 at 5:38 pm

Many of us assume that our battery is dead when our car doesn’t start. However, the alternator plays a key role in the running of your vehicle’s electrical systems, and in the replenishing of power to your battery.  If your alternator is giving you trouble, you might have experienced one or many of these four signs of alternator issues. Read on and see if it’s time to schedule your service appointment!

Buy Volkswagen Replacement Parts Online Seattle WA

4 Signs of a Failing Alternator

Flashing Dashboard Warning

Many of the newer cars out there will flash a warning light that says ALT (alternator) or GEN (generator) if your alternator is experiencing issues. This will most likely pop up when you’re using multiple electrical components at the same time. Just because it doesn’t come on every time you drive, it doesn’t mean you don’t have an alternator issue.

Hesitating or Not Starting

If your car isn’t starting, it doesn’t necessarily mean that you need a new battery. Your alternator is supposed to recharge your battery after it starts your vehicle, and if the alternator isn’t working properly, your vehicle will either have a very weak start, or won’t turn over at all. To check this, charge your battery and then try to start your car. No start with a full battery means alternator issues.

Strange Sounds and Smells

Inside the alternator, there are bearings and belts involved that can wear out. If you start to smell burning rubbed or hear a grinding and whining sound, it is worth your time to take a look under the hood for loose belts or to see if anything is worn out. Not sure where to look? Let us take a peek for you.

Dimmed Lights

Since your alternator works to power all the vehicle’s electrical systems, a pretty reliable sign for alternator issues is dimmer lights inside and outside your vehicle. Whether it’s your dashboard or headlights, dimming means an alternator issue. It might also affect your power windows and seats, so try those out to see if you can feel a decrease in power.

Volkswagen Service Tips and Info

25 Responses to “How to Tell if Volkswagen Needs New Alternator”

  1. Barbara says:

    I have a 1970 Vw beetle dune buggy with rebuilt engine n transmission in 2015. She runs great but keeps killing the battery. I have a brand new battery. I have a brand new starter. She works great as long as I disconnect the battery after every use. Otherwise the battery is dead the next time I try to start her. I thought I needed an alternator. What’s my problem And how do I diagnose it to fix her?

  2. Michael says:

    Sorry, but I think you misstated your last reason for it being your alternator. If your car won’t start or hesitates to start and you then fully charge the battery and it still won’t start or hesitates, It’s NOT the alternator! It’s the starter! If your car hesitates to start or won’t start and you then charge your battery fully and it starts normally, most likely it ‘s your alternator…

  3. Michael says:

    Sorry, but I think you misstated your next to last reason for it being your alternator. If your car won’t start or hesitates to start and you then fully charge the battery and it still won’t start or hesitates, It’s NOT the alternator! It’s the starter! If your car hesitates to start or won’t start and you then charge your battery fully and it starts normally, most likely it ‘s your alternator…

  4. Michael says:

    Barbara, I’d check the voltage regulator and the Alternator/regulator wiring. It may be wired wrong. One way to check is to charge the battery and then take the ground cable off the battery and let it set a couple of days or a week and then reattach the battery cable and see if it starts normally. I see your already doing this so, check or have someone check the regulator and wiring. I could be either one. I hope you find the problem and I hope this helps.

  5. Cecilia says:

    I have a 2007 VW Jetta Wolfsburg Edition. Yesterday evening leaving work for home, the ignition clicked a few times upon starting and was a little rough turning over, but started. It did this again leaving from a couple of stops on the way home. This morning, the car started fine, no problem. The battery in my car is only two years old (with a 3/5 year tapering warranty from Autozone). I stopped by Autozone to have the battery tested on my way home from work today and the voltage was onlty 10.55 and the results of the test were that the battery state of charge was too low for diagnosis (this was after driving it for nearly an hour to Autozone). The Autozone rep said he could not tell whether it was the alternator or the battery giving me a problem without having the battery fully charged, but they did not have the ability to charge it. It started up right away after the test and I drove home. Any suggestions of what the issue could be? Tomorrow morning I plan on dropping it off somewhere that can fully charge it to see if they can get a diagnosis.

  6. Brian says:

    Barbara, you could also have a mild short or something that is using phantom power. A short could be as simple as the starter wire being pinched against the frame of the car (this was my case and caused my grief for many years). Phantom power is something that is using power while the key is off, radios are the usual suspects of this or amps that aren’t wired to shut off when the radio is off.

    To check, get/borrow a multi-meter with a 10amp setting. Refer to the instructions on how to configure the leads and the meter for amperage testing. Then pull the negative battery cable off the battery and connect the meter in series (one lead to the battery, the other lead of the meter to the battery cable). If the meter reads above 50ma, you have phantom power that can slowly drain the battery. To troubleshoot what is using that power, have someone pull each fuse until you see the reading drop below 50ma. Then put all the other fuses back in and check which device(s) was/were hooked to that fuse. If all fuses are pulled and the meter still reads high, you have a short somewhere in the main wire, could be a bad connection, could be a frayed wire against the frame somewhere.

  7. Ashley says:

    I have a 2015 Jetta that I just purchased 2 weeks ago. Since then, I’ve taken it to 4 different shops to determine why my car is having trouble starting and no one can find anything wrong with it. It is keyless ignition and sometimes takes over 5 minutes to get it to start. Any idea what could be wrong? The alternator, starter, and battery have all been tested and determined good.

  8. Aldin Hurko says:

    I believe it could possibly be a problem with your alternator or if that isn’t it then maybe check you wiring of the keyless start

  9. Josh says:


    I have a 2010 SCIROCCO 1.4 TSI.

    I’ve got a brand new alternator and battery however the alternator still doesn’t charge the battery.

    I can see where the alternator wire connects to the fuse box however I can’t seem to locate the alternator fuse? The alternator wire fixes to a metal plate along with what I believe to be the ESP system and Electronic Power Steering.. I’m wandering if the metal plate is the fuse? Can someone please confirm?


  10. Josh says:

    Just to add, the car starts and runs for about an hour after the battery has been charged but then dies and I get a lot of lights on the dash which is why I’m assuming the alternator isn’t charging or powering the electronic components in the car!

  11. Lilian says:

    I have a 2006 vw passat my cars been fine but lately my battery has been dying i couldnt get a jump start to start it up … I took it to orielly and tjey recharged my battery and said my battery was fine i put it in my car abd my car seemed to struggle staying on at first it was fine for 2 days abd now my cars dead again any help??

  12. Joshua says:

    I have this Volkswagen Passat 2.0T 2006 model. If I make use of a new battery to start the car,the car will start immediately But if I try to off the ignition and try to start the car again ,the battery will have been drained just within 5 minutes of start the car .
    Please I need your contributions and suggestions. I have know idea what this problem could be. Thanks.

  13. eric says:

    im driving a vw 2008 1.8 turbo , my battery is still new about a month old , but in the morning
    id struggle to start , what can be the cause of that

  14. Tre says:

    Alternator fuse

  15. Paul says:

    Question for everyone. I have a 2012 GTI. My car starts ok, but after it warms up, there is a loud whining coming from the alternator area. When i accelerate, the noise dies down, but under no load or neutral it comes back in full effect. My car will also rev between 800 rpm and 1400 rpm with no pressure on the gas, when i put the car in neutral and coast. I replace all of the belts approx 35k miles ago (my car has approx 106k) and they don’t appear to be frayed. I’ve seen several comments regarding whining while accelerating, but i have the opposite. Thanks for reading and any assistance.

  16. Bartholomew Wilson says:

    I have a 2004 vw touareg. Lately, the alternator started coming on automatically, even while the ignition is off. Once it does that my battery runs dead and the car wouldn’t start until I recharge the battery. Two days ago, I noticed that even after the car has started, the alternator refused to come on…but all electrical system are still working. Except that once I stop the car, in less than an hour the battery runs dead again.
    Any idea what might be the cause for this?

  17. John Razo says:

    Anybody have a same “one click” issue when trying to start car ?? I have a vw mk4 gti 05 and the only way to turn it on is to push start it throw it n first pop the clutch n turn the key tested the battery and alternator and starter ??

  18. Nader Najjar says:

    I have a Passat CC 2.0L, 2010, the car doesn’t start, battery 6month old, we test the alternator, its 13.4V is that the standard please or its a battery issue ?

  19. M Maritz says:

    While driving passat tdi cutting out and altenator ligt come on…many tries and start again…but agter few meters cutting out again..plz help

  20. Charles M McAfee says:

    1970 VW motor , 1600cc,57 Hp. Had starter check Got an OK on starter. Re-installed starter with good ground. Got nothing. Put in new regulator, making sure ground is good , polarized reg .Got nothing. Last fall car would start sometime with a little push and pop clutch. Now I get nothing, no clicking with starter. Think it might be ignition issue.

  21. Celia says:

    Hi, I have a 2007 volkswagen jetta, my friend gave my car a jump, it would run for a few minutes and turn right back off. I called a tow truck campany to tale my car to the shop. The mechanics at the shop said when they put a new battery on the car, it started to spark as if their was a shortage somewhere in the system and said I need to take the car to an electric shop. I am trying to understand why now its an electric issue

  22. Roger says:

    my abs is always on and braeks noise

  23. Sue says:

    I have a 2007 Volkswagen Jetta Wolfsburg edition. When I got it it was drivable. It had a little trouble starting so I suspected the crankshaft sensor. I replaced that and it didn’t help. I then replaced the mass air flow sensor and my fuel pump. Just to rule it out I went to my local Oreilley’s and had my battery tested. It needed a good charge and was a little low on water but was good. When I got home and replaced the battery I tried to start the car and it turned over just fine. The car idled for a few seconds then died. I could use some advice!

  24. Jesse says:

    I have a 2013 vw Passat TDI diesel the belt shredded but all pulleys are fine so I put a new one on and car will start for 1-2 seconds and the shut off

  25. Ed valda says:

    I have a 2003 Passat wagon , my on board computer light is very dim , I checked in the internet and I see many complains about this but no one tells me what to do ?….

Leave a Reply