2003 A4 1.9TDI Alternator

[AC123]

Hi

A few days ago the battery light flickered on in my A4. Since then it is now on all the time.

This to me points to the battery not charging, and hence the alternator?

I've done a bit of a google and read something about an alternator clutch? Am I better just changing the whole alternator?

This is a video of it:

The screwdriver can just stop the internal spinny thing (the technical term for it). When the battery starts charging again the screeching stops.

Any help appreciated.

Thanks

[E-bmw]

It just comes up as a pic for me.

[GreenV8S]

The symptoms would fit a failed alternator clutch. If your car uses an alternator clutch, I think that's a safe diagnosis. You would need to remove the drive belt to replace it which gives you an opportunity for a more definite diagnosis with the engine stopped (poking screwdrivers into a running alternator is really not a good idea).

If it is just the pulley that has failed,you only need to replace the pulley and this will be much cheaper than replacing or reconditioning the whole alternator.

If you replace it yourself you'll need special tools to turn the pulley relative to the alternator shaft.

[CarsOrBikes]

Mine went, groany type noise, pulley clutch failed, inexpensive.

[AC123]

Thank you.

When you say it's inexpensive, would it be cheaper replacing the whole thing with a £40 second hand unit or not?

I don't have any specialist tools but have changed an alternator on a different car before

[GreenV8S]

I don't know about that car specifically, but for this type of thing you could pay £100 from a main dealer or perhaps a quarter of that for a pattern part. You'd have to look up the tools required to separate the pulley from the alternator but they might not be cheap. If you can get a good second hand unit for £40 that would probably work out cheaper, although bear in mind that leaves you with an old part not a new one.

[Sardonicus]

Best not stick in a screwdriver while its rotating if you get it wrong and the sprag clutch was seized for example (usual failure) not only would you do permanent damage to the alternator but could also cause yourself permanent injury you check them stationery never running they are not hard to diagnoiss anyway supply and fit usually come in at about £90 INA are usually OE factory fit available from ECP etc

[CarsOrBikes]

I'd buy a pulley from ECP, take the alternator off myself, and if no special tool, take it to a local garage who will have, to swap the pulley, refit, sorted.