Hey guys my battery light was on this morning and my serpentine belt tensioner has been broken wobbling around. Would this cause a battery to be under charged, along with my cv axel bearings falling out this morning then my car started running half power before i got home, abs started flashing slooow and air bag light came on... turned the car off. Now its dead. I have some work to do. Any advice on what to replace in terms of the drive belt system and the difficulty?
Did you take a look at your serpentine belt? A failed alternator pulley will cause the tensioner to "wobble" and often will cause the belt to break..it can also break the alternator shaft or in rare occasions on these, it can freewheel and cause a no charge.
I assume this is on your 2000 Jetta TDI? That one isn't a very easy one to do the alternator or the clutch pulley, but it is possible still. I would do some looking, make sure the serpentine belt is there still first, then check for power at the alternator as another common failure is the fuse box on top of the battery. The alternator cable gets high resistance and heats the fuse box up melting it and causing there to be no charge as well.
If the clutch pulley has gone too far, the whole alternator will need replacement, as it can damage the shaft.
Also a good thing to note, don't get an aftermarket alternator or clutch pulley. The difficulty of the job combined with how long the aftermarket ones last (often less than a year) as well as the relatively low cost of OEM parts, its really a no-brainer.
An oem clutch pulley is $35, and a remanufactured alternator with all oem parts is less than $200.