2000 Jetta 2.0 Alternator Output?

Hey All,

Does anyone know what a completely stock 2000 Jetta 2.0 (manual) alternator puts out in the way of amps?

I have a couple of amplifiers hooked up in the car for a stereo system, and I've noticed that when I'm running the stereo a loudly the headlights dim a bit.

To get some obvious stuff out of the way: I've been doing car stereos for more than a few years, and understand that headlight dimming is not the end of the world, but I want to make sure that everything is up to snuff. Specifics? The lights dim only at higher volumes, but once those volume levels are reached they dim no matter what the RPMs are at (though, the higher the RPMs, the less time the dimming lasts). I'm using one amplifier to push one 10-inch subwoofer (at 150 watts, RMS, if anyone cares), and a different amplifier to push the two rear speakers (at 60 watts each, RMS). The two amplifiers have a combined MAXIMUM current draw of 36 Amps (14 for the subwoofer, 22 for the rear two speakers). On top of that, the deck itself is powering the front two speakers, therefore taking up power as well. There is, of coarse, all of the other normal power being used by the car as well.

So, what I'd like to know is whether or not my stock alternator should be up to handling this load. If it's supposed to be putting out more than enough power (doubtful), then I can take the car in for a little check up, and have the alternator and battery looked at - then have the faulty part replaced. Unfortunately, I suspect that I may be pushing (or exceeding) the limits of the power capabilities under my hood.

My next question is this: If the stock alternator for my car isn't supposed to be handling such loads (likely), I have three options for dealing with the power drain - and would appreciate input on these options.

1) Quit worrying about it, and leave it alone and deal with headlight dimming. 2) See if an alternator is available that puts out more power, and implement it if possible. 3) Install a capacitor for the stereo.

Each option has its drawbacks, but each also has specific advantages.

Anyone up for this discussion?

~The Lull

Reply to
The Lull
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should be a 90amp, but VW also had some with 120A but I think they were for the 1.8t engines.

Reply to
Lost In Space/Woodchuck

Okay, well that's more than I thought it would be...

So with that k> should be a 90amp, but VW also had some with 120A but I think they were for

Reply to
The Lull

Don't you need stiffener caps at that kind of load?

...Sean.

Reply to
Sean

watts = volts xamps , you do the math , Option 4 . turn the freakin stereo down

Reply to
samstone

Let's say:

Normal vehicle draw (engine, ecm, all the bits and pieces) 20 amps.

2 headlights at 5 amps each (total 10 amps) 6 Misc exterior lights at 1 amp each (total 6 amps) 10 interior/dash lights at .5 amps each (total 5 amps)

Heater fan medium speed 12 amps (yes, they do draw a lot of current).

Battery charge 7.5 amps (if the battery is not discharged badly)

Radio/head unit 8 amps Sound amplifiers (your numbers roughly) 36 amps

That's 104 amps... (bet I missed a few things that are drawing current too!)

I'll bet your lights dim when the amps are putting out a lot of power, right?

(Oh, and that 90 amp alternator isn't really going to like putting out

90 amps full time, either, but that's a different matter.)

Some ideas: Bigger alternator (of course) at least 140 amp version. Led running lights will save a few amps there (I did this on a truck that had a bazillion running lights and foudn the savings was incredible!)

Check the wires between the alternator and battery for size--if they are too small you'll see just this type of operation. Especially if you go to a bigger alternator.

Reply to
PeterD

These are only useful *if* the alternator can provide the average power, and his can't do that.

Reply to
PeterD

Wow. Great way to put things in perspective, and point me in the right direction.

Thanks Pete!!!

Reply to
The Lull

You'll miss your hearing when it's gone.

Mike

Reply to
upand_at_them

What?

Reply to
samstone

Reply to
tacurong

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