To all those who responded.
If you had a voltmeter , a systematic check would have revealed the
alternator had gone bad. 
I took the short cut and went and bought a voltage regulator but the
problem was not it. Well got to pay for one's weakness sometimes.
Anyway for the benefit of members reading, when you observe that the
alternator light is at half brightness with ignition on(engine not
turning) its a bad alternator. Even when the engine is started, the 
light remains same without going out. The Bentley manual does not
describe this condition specifically.
On shopping for parts these were the prices:
Voltage regulator Bosch (not available)  $80.00
		  Borg-Warner after market $35.00
                  (good to keep as spare in the vehicle)

Alternator Did not try VW, must be over $200.00
           Pep Boys   $149.00 with exchange
           Strauss Stores $225.00 with $90.00 credit for old unit.

	   Wrecker Audi unit but have to remove the pulley
                   ( a pain in the butt to remove, had to purchase
                     a #24 mm socket, $5.69 from Sears for this job)
					Cost $35.00
	Thanks again to everyone who responded.
					Terry Tan