Battery not charging? Anything special to check?

[atomicalex]

1998 AFNii German-market 110hp TDi.

Battery is no longer being charged by the car, or the charging is not occurring over a normal 20 minutes drive. Battery takes a charge from the charge-box just fine, car starts great on the charged battery, all is good there. I can get two starts per charge, assuming I don't run the lights at all.

Aside from chasing down an exciter wire issue and getting the alternator tested (FML, how do I do that in Germany?), is there anything else I should look for? I've got decent VW chops, but I'm a MkIII n00b.

[atomicalex]

Exciter wire was split, fixing that now. But no light on dash. Pulled cluster, put good light bulb in. Will check that in a few minutes.

Would a long-term bad exciter wire give the voltage regulator issues?

[atomicalex]

Ooooh, look at the pretty battery light!!! I can begin alternator diagnostics once I charge the stupid battery now.....

[Sallad]

One way to test the alt, while the car is running, put a meter on the Barry posts (center of the post) and read the voltage. It should be around 13.5 - 14.5 volts.

Then start turning on all your lights and radio, the voltage should not drop.