2g 4g63 alternator or battery?

[slo95tsi]

I have a 1995 Tsi Awd and was doing some work on it today. My crank pulley separated a week ago so i replaced the crank pulley and the alt belt today. Now my new problem ( surprise surprise!) is that after I replaced the alt belt and crank pulley i went into my car and turn the car to 'on' and all of my accessories, power windows, locks, lights, gauges, cd player would not light up. Headlights not working as well. I looked at the dash and I could barely see the lights on, BARELY. Everything was dead. (note: I did remove the neg terminal of my battery before i was working on all of this just to be safe.)

Now im guessing its either my alternator, battery (which is farely new) or my alternator fuse. I got a jump start from a friend and my car started up fine besides a squeeking belt, i can tighten that. My dash, all interior lights, cd player, headlight were bright as can be. My car wont stay on though, it'll just die after like 30 seconds if it isnt hooked up to another cars battery. Hopefully its just that 100A alt fuse in the fusebox. Im going to replace that tomorrow and see what happens. Anyone have any ideas? I should replace the alt fuse first then if that doesn't work take the battery in to test it and if that doesn't work, take the alternator in? Thanks in advance guys!

 

[squeak104]

It sounds like your alternator isn't charging. After the car is jumped and running and you unhook the other car the engine uses what little power the battery has then dies. If you have a multimeter, hook it up to the battery while its running and that will give you a quick reference if the alternator is charging. Looking for 13-14 volts.

 

[slo95tsi]

okay so if i do get a reading of 13-14 volts then its my battery correct? If not, then its my alternator right? thanks again!

 

[streetxtreme]

its should be 14.6 v with no accessories turned on
with heater motor and headlights (or anything that takes more power) turned on, it should drop no more than 13v

12.6 v is battery voltage when fully charged and if your getting equal or less when measuring, then it won't charge

 

[djjohns55]

Did you check the alternator plug on the alternator?
There is a simple test to check if its the battery or the alternator
1.Start the car
2.unhook the batteries hot wire
3.see if it shuts off.
//if the car shuts off then your alternator isnt charging
//else if it runs good your battery isnt any good.
Since your alternator is fairly new it sounds like the alternator plug is loose if the fuse isn't bad.

 

[95talon07]

i had the same prob and it turned out it was the alternator. changed it out and now it runs beutiffuly........ for now

 

[squeak104]

Don't unhook the positive cable while the car is running. It can cause voltage spikes. And yes if you are seeing low voltage then your alternator isn't charging. To be certain run a big wire, such as part of a jumper cable, from the positive terminal on the battery to the stud on the alternator where the white wires connect to it. Make SURE if you use a jumper cable that the clamp doesn't touch the case of the alternator or any other metal part of the car or the wire will get really hot really fast. Then check the voltage again to be sure that there isn't an open in the wires.

On a side note, I would still take your battery in to be tested. From all the times of cycling it from voltage to no voltage could have killed it. If nothing else the tester, or at least I know for certain the one at Advance Auto, will recharge the battery.

 

[slo95tsi]

update** thanks for everyone's help! i greatly appreciate it all! so i just tried starting the car without any jumpers just by itself and it doesn't even make any sounds. Its dead silent. Still no lights no power at all, doesn't even try to crank over, just dead. I turn it over, nothing, dead silence. This has to be the battery gone bad right? (note: today was the first time I tried starting her up in about 3 weeks).. Firs thing tomorrow is get a new alt fuse, (any other fuses i should check for?) and take the battery in to get tested! I hope its just the battery thanks! anymore help would be appreciated!!

 

[squeak104]

It could be this or it could be that. Diagnose the problem before you start throwing parts at it. Diagnosing is what seperates the parts replacers from the technicians. But if you want to waste $4 on a fuse go ahead but you've been given a procedure of how to diagnose your problem before you buy any parts. Good luck.

 

[streetxtreme]

also, if the weather is cold like here in toronto/canada
the battery acid can freeze on cheaper batteries
therefore causing you to have no lights
when you have no lights, that means your battery is very low on charge

if it is a maintainence type battery, you can pop open the plastic cover thats on top of the battery and see if the fluid is frozen, if it is, the battery will not accept the voltage even if the alternator tries to give it.

either way, diagnosis is the way to save lots of money and headaches
jump start the car
remove the cables from your friends car
if the car still runs, check the voltage at your battery, if it is 14v, you've eliminated the alternator

 

[streetxtreme]

there was a time when i replaced a battery with the CHEAPEST BATTERY i could find at parts source
the battery was frozen 2 weeks later
and broke the battery casing
acid leaked everywhere after the acid melted

even i new battery can be faulty in some cases,
thought i share this experience with you

 

[slo95tsi]

thanks so much guys for all of your help again!! that is true diagnosis ftw! i've got a battery voltage reader on my turbo timer, would this be a good tool to use when reading the voltage after i remove the jumper cables? im still a little confused, so if the reading does give me 13-14volts then its my alternator thats bad? or my battery thats bad? just making sure so i dont go out and buy unnecessary parts! thanks

 

[squeak104]

Not too be rude or anything but its not the acid that freezes. When a battery gets low on charge the water and acid seperate and the water freezes, usually causing the case to swell or break.

Yes the turbo timer should be good enough for measuring the voltage. If you get 13-14 volts then you are charging fine and may have other problems. If the voltage is that much post back and we can help you diagnose from there.

 

[streetxtreme]

Not too be rude or anything but its not the acid that freezes. When a battery gets low on charge the water and acid seperate and the water freezes, usually causing the case to swell or break.

last time it froze, i just popped it open and looked in
it looked like everything was frozen solid in there, didn't look like it was separated or anything
i think the case breaks from the expanding of the liquid, which puts pressure on the battery case

i could be wrong about the separation part

but either way, if the battery freezes, you will get a very low charge on your battery, if any.

 

[streetxtreme]

Yes the turbo timer should be good enough for measuring the voltage. If you get 13-14 volts then you are charging fine and may have other problems. If the voltage is that much post back and we can help you diagnose from there.

(please don't take offense here, I'm just sharing my thought/experiences)
13v might be a bit low
a fully charging alternator should give you 14.6v
if your getting 13, there might be some high resistance in the main wire or corrosion in the terminals
or you might just have all your electronics turned on (headlights, blower motor, turn signal etc.)

but anything above 12.6 v and you will know that the alternator is NOT DEAD.
if you get more than 12.6v, you know that voltage is coming from somewhere else (alternator)


if you have cold weather where you live , you might want to check to see if the liquid inside the battery froze .
if its frozen, handle the battery with a pair of thick rubber gloves (dish washing gloves are good), because there might be battery acid all over the battery

last time this happened to me, i burned my hand without knowing it

 

[slo95tsi]

update** i took my battery to autozone, it was completely drained so they recharged it up for me for about an hour. They said it charged up fine so i took it back hooked it up and all of my accessories now work, power windows, locks, lights and cd player!

On my turbo timer it fluctuates between 12.4 - 12.56 volts. Thats when its just sitting there, the car not started. Is this bad? I havent tested it with the car started b/c i have to go to class really quick and i still tighten my alt belt. Ill be back in about 2 hours and give an update..

 

[slo95tsi]

***update again! great news!! shes up and running again!! It was the battery not the alternator.. it read out 13-14volts when its started.. I guess all it needed was a charge! Thats for everyone's help and support! You guys and this forum really helped out a lot! I appreciate it all! thanks!!