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Discussion Starter · #1 ·
2004 V6 4motion

Hi folks,
My story begins about 12~13 months ago. I'll state the facts, and you can tell me if these issues are from a possibility of one source, or if I may likely have multiple problems.
13 months ago the car would sometimes need more than one turn of the key to crank, until one day, it wouldn't crank at all. At that point, I had a German car specialist change the starter. After that, it would start the vast majority of the time on the 1st try, but not every single time.

Beginning about a month ago, I would have to turn the key twice to get it to crank & start. But it would always crank & start on the second try. Keep in mind, this is a no crank issue.

Trying to eliminate the possibility of it being a fuel issue, I once put the key in the on position three times before cranking (thinking to activate the fuel pump and pressure), but it still required a 2nd try.

Since last week, as I was bringing it home, the ALTERNATOR WORKSHOP light came on along with the BATTERY light.

I hooked up the some wires from the battery to inside the cabin and then hooked up my multimeter so that I can read the battery terminals while driving or revving the engine.
The readings do fluctuate from 11.xx to 14.xx volts. Readings usually increase with RPM's but not always.

Those are the facts, below are the questions.

Can it be said with 100% certainty the alternator is bad?

In trying to determine if this can be only a bad alternator and not other faulty parts as well:
I was told by a AAA tech that a weakened (undercharged) battery could require you to need two key turn attempts. I was told that the first try “excites” the battery, and then is able to crank and start the car on the second try. Does that make sense or have you ever heard of that? I’m just hoping I don’t also have a bad starter (which I replaced last year). I would have thought that a weakened battery would at least crank.

I don’t want to get stuck if I were to attempt this. I can easily remove the bumper and the bumper support, removing the serpentine belt is very easy.
The only part that may cause me a problem is to pull out the alternator and to put it back in (having an injured shoulder isn’t helping). How hard is it to pull these units out? I guess that would be the hardest part of the job (from what I read here). And putting them back in as well?

You must drain the coolant also? I read it both ways (yes and no).
If so, will putting new coolant be a two hour job with burping and adding and burping and adding?
If I have to replace coolant, would it be worth it to just swing out the whole radiator to access the alternator? Would that be easy?

Since I bought this car (almost 2.5 years ago) it used to make a high pitched sound sometimes going up a hill or if I revved it in neutral while parked. If I do fix this, I am wondering if that sound was indeed the alternator. I never figured out where that sound was coming from, though I tried!

Recommendations on where to buy and not buy an alternator?

Thanks if you made it this far! It’s just that, this seems to be a hard fix, and a starter and an alternator will be more to fix than what my car is worth. I don’t know if I should think about throwing in the towel yet.
I can be handy, but this car is challenging to work on.
Maybe, as long as I don’t have to fight or use a lot of force, it won’t be so hard.
Sorry for the long post and my OCD. I'm gonna be banned for such a long post and so many Q's...

Thanks again!
 

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in dire need of an organic chemistry lesson
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I would say it's a challenging job to a certain extend. You need to remove the radiator fan clutch to get the alternator out.
If you really wan to be sure alternator is dead or half baked you need to measure the voltage at battery terminals when the engine is running. It should be 14+ volts.
There are a few options if it's dead. 1) buy a new one. The genuine OEM at stealership is pricey. 2) buy a non-OEM new one. Almost certainly it's Chinese made and whether it will last is a big Q.
3) Buy a used rebuilt one. Or picking up one from the nearest junk yard. These are much cheaper but their durability is a Russian Roulette. 4) Take your's out and change their brushes and they become like new. Ask ylwagon for instructions as how to do it. New brushes cost only a few bucks. Note that even with new brushes, its internal bearing may still jam in which case you definitely need to replace it entirely.

For this job I don't believe the coolant needs to be drained but others may chime in and advise.
 

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Emry, car is a V6 so the fan isn't involved.

Trying to eliminate the possibility of it being a fuel issue, I once put the key in the on position three times before cranking (thinking to activate the fuel pump and pressure), but it still required a 2nd try.
We need to agree on the word "cranking" first. I understand that to be when the starter motor runs and rotates the crankshaft. Is that exactly what you mean?

I hooked up the some wires from the battery to inside the cabin and then hooked up my multimeter so that I can read the battery terminals while driving or revving the engine.
The readings do fluctuate from 11.xx to 14.xx volts. Readings usually increase with RPM's but not always.
When measuring battery voltage, it may be easier to probe the 12V accessory 'cigarett lighter' socket than running wires to the battery. Voltage will measure exactly the same if that circuit isn't drawing current.

Can it be said with 100% certainty the alternator is bad?
No, electrical connection problems at the alternator or elsewhere can cause it not to charge.

I was told by a AAA tech that a weakened (undercharged) battery could require you to need two key turn attempts. I was told that the first try “excites” the battery, and then is able to crank and start the car on the second try. Does that make sense or have you ever heard of that?
Maybe if the battery was very cold, and the first try warmed the electrolyte up. But your voltmeter test would reveal that.

You must drain the coolant also? I read it both ways (yes and no). If so, will putting new coolant be a two hour job with burping and adding and burping and adding?
No, the coolant doesn't need to be drained unless you want maximum working room between the radiator carrier and front of the engine. And putting new coolant in is a 15 minute job, if done correctly.

Recommendations on where to buy and not buy an alternator?
Usually a non-charging alternator only needs new brushes, or a brush-regulator assembly, to work again. I have changed just brushes on our 1.8T as Emry said, but buying the regulator is easier and avoids the fitting of motor brushes and soldering. If you buy a new alternator, perhaps one of the common on-line retailers such as FCP Euro, ECS tuning, Autohausaz, etc.
 

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Discussion Starter · #4 ·
TONY! said:
Trying to eliminate the possibility of it being a fuel issue, I once put the key in the on position three times before cranking (thinking to activate the fuel pump and pressure), but it still required a 2nd try.
We need to agree on the word "cranking" first. I understand that to be when the starter motor runs and rotates the crankshaft. Is that exactly what you mean?
Sorry for the confusion. Yes, you are correct.
I put the key in the on position three times, and then to the start position.
The problem with the car (one of the problems) is that when you go to start it (maybe from the cold), on the first attempt, nothing happens. I don't even think I remember hearing a click. No starter motor turning noise, possibly no clicking (solenoid) noise, nothing.


Before I even take it anywhere....I just wanted to make this thread and ask yous....though I may work on it myself (not sure yet).


Thanks for all the advice!
 

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I guess the age is kicking in :p
Many of us get in the mindset of a certain engine when replying. Can't tell you how many times I typed out a full reply and then just canned it when I saw it had nothing to do with a V6 :rolleyes:

To the OP. As has been said, many times, a simple changing of brushes or the regulator assembly will fix it; provided it is the alternator and not connection related. I rebuilt a replacement 120a unit with new bearings and brushes (slip ring was fine).
 
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Do the dash lights come on when the key is 1st turned? If not, there is a good chance it's the ignition switch. If they do, you may have a wiring issue, either a bad ground or a bad braided lead from the starter relay to the starter body.

The alternator problem may be related if it's a bad ground. Usually alternators fail completely, not intermittently. A bad ground would explain that and save you having to replace the alternator. If the alternator is still bad, replacement is a hassle. Depending on your shoulder issue, it may be too much. You need to be able to place the car in service position, remove the bolts either from above or below and remove the wiring from below. It's not a lot of force required, but working below a car with a dislocated shoulder (as I done) is painful.
 

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Sounds like you may have two issues. First you had a no start issue and as PZ suggested this may be the ignition switch. Then as time has gone by you have also developed as alternator issue.
As recommended above you need to do a little testing before throwing parts at the issues.
The ignition switch is pretty easy to change out and there are diys and videos if you search.

The Alternator on the V6 is a real pain to get out and just as much fun to get one back in. In my case all I replaced is the voltage regulator on the back of the alternator which is much less expensive at only $50 for the Bosch part. Yes you still need to remove the alternator to replace the regulator.
Takes about 2 hours to remove the alternator, 5 minutes to replace the regulator and another 2 hours to button everything up. There is also a diy for the alternator job.
Oh, and before you go the the work of putting everything back together. It's worth the trip to the local auto parts store to have your repaired alternator tested.

Not going to be any fun at all with an injured shoulder.
 

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For what its worth, when I had the motor mount bracket on the passenger side removed while changing the motor mounts (on my B5 Audi), I remember noticing that the alternator looked to be fully accessible. If that were true, it might be quite a lot less work to support the engine and remove the bracket, than the usual method.
 

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Not related but is it possible to use a 120A alternator on a 1.8t, which normally uses 90A?


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It's been done, but I forget if it was just a pulley change or if the harness needed to be swapped too.
 

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Not related but is it possible to use a 120A alternator on a 1.8t, which normally uses 90A?
It depends on how the car pulls the amps from the alternator. If the alternator generates 120A but the car sucks only 90A out of it then there's no issue. But if the alternator pushes the 120A into a 90A circuit it may be problematic in terms of the wires get very hot or even catch fire. I would go with the manyfacturer's spec in this case. Why risk?
 

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A 120A, 12V alternator, or for that matter a 1,000 Amp-capable 12V alternator, won't 'push' more current than a 90A, because the 'push', which we call Voltage, is basically the same in all cases- as long as the car's electrical system is stock*. If the load for some reason exceeds the alt's current capacity, then the battery makes up the difference. But I agree; keep the stock alternator unless there is a special situation like charging extra batteries.

*An extremely dead battery may take more current from the 120A than the 90A, until the battery's voltage raised to the normal range. The resulting extra heat might not be good though.
 

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It's been done, but I forget if it was just a pulley change or if the harness needed to be swapped too.
Just a pulley change.

I will run a higher amperage for a few reasons.

My Passat only gets driven maybe a couple times a week and a lot of that is short trips with many start and stop cycles. Just a little extra insurance to keep the battery topped up and in good condition.

Higher current draw from accessories in everyday driving:
  • Replacement speakers and sub with amplifier totaling ~600w RMS (30-35 amps draw max)
  • Upgraded some things from GLS trim to GLX like power seats and whatnot
  • Removed the fan clutch and installed an electric fan instead

I figure radio is about 5A, defroster 15A, A/C 35A (both fans on), headlights 11A, audio system ~24A = ~80-85A and that's not counting the load the coils and injectors draw.

Here's a good link to figure some things out. https://www.aa1car.com/library/electrical_amp_loads.htm

The wiring gauge is within spec for each of the components connected. If anything would need to be upgraded, it would be the "Big Three"; alternator to the battery, battery to ground, and engine to ground. I might as well do while there. https://www.passatworld.com/forums/...09218-updating-electrical-system-big-3-a.html

Besides, its like using a charger for your phone. 1.5 vs 2.1 vs 2.4. If your phone only charges at 1.5A, it will charge at that rate, even if you use a 2.4A charger. It is supply and demand. It will only put out as much amperage as it being asked to.

Sorry, swayed a little OT.
 
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Discussion Starter · #16 ·
Thanks for all your help, attention (to such a long post), and tips.

I've been researching some of the things that I've read.
(I am mechanically inclined, but electronics is my weakness.)

VAGguy said:
...
As has been said, many times, a simple changing of brushes or the regulator assembly will fix it; provided it is the alternator and not connection related.
...
I just watch a youtube video about how to replace that. I guess I'll figure out if my exact alternator has such a part available for sale somewhere.


PZ said:
Do the dash lights come on when the key is 1st turned? If not, there is a good chance it's the ignition switch. If they do, you may have a wiring issue, either a bad ground or a bad braided lead from the starter relay to the starter body.

The alternator problem may be related if it's a bad ground. Usually alternators fail completely, not intermittently. A bad ground would explain that and save you having to replace the alternator. If the alternator is still bad, replacement is a hassle. Depending on your shoulder issue, it may be too much. You need to be able to place the car in service position, remove the bolts either from above or below and remove the wiring from below. It's not a lot of force required, but working below a car with a dislocated shoulder (as I done) is painful.
I tried to start the car today, and again, on the 1st try, nothing.
The dash lights were on, but I am not 100% sure that they dimmed (I think they dimmed at the first attempt, but not sure).

If it means anything, I don't start this car every day (especially now--it is just sitting and waiting for me).

I guess I'll get under the car and inspect the wires then.

The shoulder issue...I have yet fully understand my issue despite X-rays and MRI images (I hope I don't have a tear).
I've been diagnosed with a lot of different things.
I think one of my tendons in the front of my arm got pinched and raked in a fall and now catches (impinges)...and maybe in time, the swelling will go down and things will move without binding.
Sorry to read about your injury, and I hope for your best recovery.
For me, I just have to never catch and aggravate that tendon under the acromion--the only way I can heal.


ylwagon said:
For what its worth, when I had the motor mount bracket on the passenger side removed while changing the motor mounts (on my B5 Audi), I remember noticing that the alternator looked to be fully accessible. If that were true, it might be quite a lot less work to support the engine and remove the bracket, than the usual method.
Now I know what my two mechanic contacts were talking about when they recommended a different method.
I think that method requires a hoist though.

In the next few days, I'll try to research and implement all the advice you folks were so kind to bestow onto me.
 

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You do have at least 2 separate issues.

1. The no crank issue is likely to be a faulty ignition switch, but there are many other possibilities.
You should check the wiring, connectors, and all components between the ignition switch and the starter solenoid.
I would start with the connector on the solenoid, that might be a bit loose.

2. The charging issue.
If you have a Bosch alternator it is probably the brushes.
If you have a Valeo alternator it might be the brushes.
You could replace the brushes/regulator in a Valeo (and probably a Bosch) without removing the alternator, if you remove the engine mount. A hoist is not required.

Note on Valeo: My original Valeo failed at about 100,000 miles with an open circuit rotor winding, and had to be replaced.
I replaced it with a rebuilt Valeo which failed with the same problem after about 10,000 miles.
I replaced that with another rebuilt Valeo which also failed with the same problem after another 10,000 miles.
With this fault, it usually starts off intermittent for a while (either normal charge or no charge) then ends up dead.

Worn brushes usually cause gradually reducing charging until there is not enough to keep the battery charged.
 

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Discussion Starter · #18 ·
First, I am very grateful for all the help and time!

To tell you what happened, I tried my best to do the job myself, but this car is just too complicated for me and so I backed out before completion.
Wrenching other cars is far easier than this one!

I took it to a German car specialist, and was with him when he changed the alternator.
The front was pulled and a fan was removed to get access (that was deemed the best way for my car).

Most importantly and now, the car starts up every time now and doesn't need a second or third try, so either....
A) this was related to a bad alternator causing the battery to be somewhat discharged (assuming that the alternator was gradually failing)
B) the need for multiple starts had nothing to do with the alternator, but happened because of the cold (I remember last year it needed two tries in the winter a few times).
 
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